Artykuły w czasopismach: „Cation and Anion”

1

Xu, Si-Yu, Zhou-Yu Meng, Feng-Qi Zhao i Xue-Hai Ju. "Density functional study of guanidine-azole salts as energetic materials". Canadian Journal of Chemistry 96, nr 10 (październik 2018): 949–56. http://dx.doi.org/10.1139/cjc-2018-0106.

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A series of guanidine cations and azole anions were designed for use as energetic salts. Their geometrical structures were optimized by the density functional theory (DFT) method. The counter ions were matched by the similar magnitude of the electron affinity (EA) of the cation and the ionization potential (IP) of the anion. The densities, heats of formation, detonation parameters, and impact sensitivity were predicted. The incorporation of guanidine cations and diazole anions are favorable to form thermal stable salts except cation A1. The diaminoguanidine cation has greater impact on the density and detonation properties of the salts than the triaminoguanidine cation. 2-Amino-3-nitroamino-4,5-nitro-dinitropyrazole is the best anion for advancing the detonation performance among all the anions. Incorporating the C=O bond into the guanidine cations enhances the density and detonation performance of the guanidine-azole salts. The salts containing III1–III4 anion have better detonation properties than HMX, indicating that these salts are potential energetic compounds. Compared with RDX or HMX, some salts with diaminoguanidine cation display lower impact sensitivity.

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Wilkinson, Hazel S., i William T. A. Harrison. "Hexane-1,6-diammonium bis(dihydrogenarsenate): infinite anionic layers containing R 6 6(24) loops". Acta Crystallographica Section E Structure Reports Online 63, nr 3 (28.02.2007): m902—m904. http://dx.doi.org/10.1107/s1600536807007672.

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The title compound, C6H18N2 2+·2H2AsO4 −, contains a network of doubly protonated centrosymmetric hexane-1,6-diammonium cations and dihydrogenarsenate anions. These species interact by way of cation-to-anion N—H...O and anion-to-anion O—H...O hydrogen bonds, the latter leading to infinite sheets of the H2AsO4 − anions.

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3

Jarjis, Hayfa M., i Salim M. Khalil. "MINDO-Forces Study of Phenyl and Cyclopropyl Substituted Allyl Cations and Anions". Zeitschrift für Naturforschung A 42, nr 3 (1.03.1987): 297–304. http://dx.doi.org/10.1515/zna-1987-0317.

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MINDO-force calculations have been performed on phenyl and cyclopropyl substituted allyl cations and anions with complete energy minimization. It is found that the phenyl ring destabilizes the allyl cations when substituted at the terminal and at the center carbon atom of the cation, while the cyclopropyl ring stabilizes the allyl cation when substituted at the terminal carbon atoms, but destabilizes the cation when substituted at the center carbon atom of the cation. These results agree with the experimental ones. In the case of the allyl anions, it is found that the phenyl ring destabilizes the allyl anions when substituted on the terminal and on the center carbon atoms of the allyl anions, while the cyclopropyl ring stabilizes the allyl anion when substituted on the terminal carbon atom but destabilizes the anion when substituted on the center carbon atom. Also, it is found that both the phenyl and cyclopropyl rings are electron withdrawing when substituted on the allyl anions, while they are electron donating when substituted on the allyl cations.

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4

Vetrivel, S., E. Vinoth, R. U. Mullai, R. Aruljothi i M. NizamMohideen. "Crystal structure of 1,4-bis(3-ammoniopropyl)piperazine-1,4-diium bis[dichromate(VI)]". Acta Crystallographica Section E Crystallographic Communications 72, nr 5 (5.04.2016): 616–19. http://dx.doi.org/10.1107/s2056989016005284.

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The asymmetric unit of the organic–inorganic title salt, (C10H28N4)[Cr2O7]2, comprises one half of an 1,4-bis(3-ammoniopropyl)piperazinediium cation (the other half being generated by the application of inversion symmetry) and a dichromate anion. The piperazine ring of the cation adopts a chair conformation, and the two CrO4tetrahedra of the anion are in an almost eclipsed conformation. In the crystal, the cations and anions form a layered arrangement parallel to (001). N—H...O hydrogen bonds between the cations and anions and additional C—H...O interactions lead to the formation of a three-dimensional network structure.

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5

McAdam, C. John, Lyall R. Hanton, Stephen C. Moratti, Jim Simpson i Ravindra N. Wickramasinhage. "Structure and Hirshfeld surface analysis of the salt N,N,N-trimethyl-1-(4-vinylphenyl)methanaminium 4-vinylbenzenesulfonate". Acta Crystallographica Section E Crystallographic Communications 75, nr 7 (4.06.2019): 946–50. http://dx.doi.org/10.1107/s2056989019007758.

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In the title compound, the asymmetric unit comprises an N,N,N-trimethyl-1-(4-vinylphenyl)methanaminium cation and a 4-vinylbenzenesulfonate anion, C12H18N+·C8H7O3S−. The salt has a polymerizable vinyl group attached to both the cation and the anion. The methanaminium and vinyl substituents on the benzene ring of the cation subtend angles of 86.6 (3) and 10.5 (9)° to the ring plane, while the anion is planar excluding the sulfonate O atoms. The vinyl substituent on the benzene ring of the cation is disordered over two sites with a refined occupancy ratio of 0.542 (11):0.458 (11). In the crystal, C—H...O hydrogen bonds dominate the packing and combine with a C—H...π(ring) contact to stack the cations and anions along the a-axis direction. Hirshfeld surface analysis of the salt and of the individual cation and anion components is also reported.

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6

King, Benjamin T., Bruce C. Noll i Josef Michl. "Cation-π Interactions in the Solid State: Crystal Structures of M+(benzene)2CB11Me12- (M = Tl, Cs, Rb, K, Na) and Li+(toluene)CB11Me12-". Collection of Czechoslovak Chemical Communications 64, nr 6 (1999): 1001–12. http://dx.doi.org/10.1135/cccc19991001.

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In these crystal structures, the relatively weak electrostatic interactions between the bulky CB11Me12- anion and the title cations permit cation-π interactions in the solid state. In all cases, single-crystal X-ray diffraction analysis reveals η6-arene-cation interactions within 10% of the expected van der Waals distance. The Tl+, Cs+, Rb+, and K+ structures are isomorphous, with the benzene molecules sandwiching the cation and four anions equatorially disposed in a nearly square arrangement. Both the cation and the near-square of closest anions are positioned to interact favorably with the local dipoles of benzene. The smaller Na+ crystallizes in polymeric chains with a nearly tetrahedrally coordinated cation in van der Waals contact with two anions and two benzene molecules in a tilted-sandwich arrangement. The Li+ structure possesses two motifs, a simple van der Waals sandwich of a toluene molecule and an anion, and chains of half-occupied toluene-Li complexes on inversion centers between anions. The simple van der Waals model is reasonably accurate for the cation-arene distances, only slightly underestimating the separation (2-10% deviation), with worse agreement for the smaller cations.

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7

Franciolini, F., i W. Nonner. "Anion-cation interactions in the pore of neuronal background chloride channels." Journal of General Physiology 104, nr 4 (1.10.1994): 711–23. http://dx.doi.org/10.1085/jgp.104.4.711.

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Background Cl channels in neurons and skeletal muscle are significantly permeable for alkali cations when tested with asymmetrical concentrations of the same salt. Both anion and cation permeation were proposed to require binding of an alkali cation with the pore (Franciolini, F., and W. Nonner. 1987. Journal of General Physiology. 90:453-478). We tested this hypothesis by bilaterally substituting large alkali cations for Na and found no significant changes of unitary conductance at 300 mM symmetrical concentrations. In addition, all organic cations examined were permeant in a salt gradient test (1,000 mM internal@300 mM external), including triethanolamine, benzyltrimethylamine, and bis-tris-propane (BTP, which is divalent at the tested pH of 6.2). Inward currents were detected following substitution of internal NaCl by the Na salts of the divalent anions of phosphoric, fumaric, and malic acid. Zero-current potentials in gradients of the Na and BTP salts of varied anions (propionate, F, Br, nitrate) that have different permeabilities under bi-ionic conditions, were approximately constant, as if the permeation of either cation were coupled to the permeation of the anion. These results rule out our earlier hypothesis of anion permeation dependent on a bound alkali cation, but they are consistent with the idea that the tested anions and cations form mixed complexes while traversing the Cl channel.

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8

Wilkinson, Hazel S., i William T. A. Harrison. "2-Methylpiperazinium bis(dihydrogenarsenate)". Acta Crystallographica Section E Structure Reports Online 63, nr 3 (28.02.2007): m900—m901. http://dx.doi.org/10.1107/s1600536807008392.

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The title compound, C5H14N2 2+·2H2AsO4 −, contains a network of centrosymmetric doubly protonated 2-methylpiperazinium cations, showing disorder of the methyl group, accompanied by dihydogenarsenate anions. The component species interact by way of cation-to-anion N—H...O and anion-to-anion O—H...O hydrogen bonds, the latter leading to infinite sheets of the H2AsO4 − anions containing R 6 6(24) supramolecular loops.

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9

Kruk, Danuta, Elzbieta Masiewicz, Sylwia Lotarska, Roksana Markiewicz i Stefan Jurga. "Correlated Dynamics in Ionic Liquids by Means of NMR Relaxometry: Butyltriethylammonium bis(Trifluoromethanesulfonyl)imide as an Example". International Journal of Molecular Sciences 22, nr 17 (24.08.2021): 9117. http://dx.doi.org/10.3390/ijms22179117.

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1H and 19F spin-lattice relaxation experiments have been performed for butyltriethylammonium bis(trifluoromethanesulfonyl)imide in the temperature range from 258 to 298 K and the frequency range from 10 kHz to 10 MHz. The results have thoroughly been analysed in terms of a relaxation model taking into account relaxation pathways associated with 1H–1H, 19F–19F and 1H–19F dipole–dipole interactions, rendering relative translational diffusion coefficients for the pairs of ions: cation–cation, anion–anion and cation–anion, as well as the rotational correlation time of the cation. The relevance of the 1H–19F relaxation contribution to the 1H and 19F relaxation has been demonstrated. A comparison of the diffusion coefficients has revealed correlation effects in the relative cation–anion translational movement. It has also turned out that the translational movement of the anions is faster than of cations, especially at high temperatures. Moreover, the relative cation–cation diffusion coefficients have been compared with self-diffusion coefficients obtained by means of NMR (Nuclear Magnetic Resonance) gradient diffusometry. The comparison indicates correlation effects in the relative cation–cation translational dynamics—the effects become more pronounced with decreasing temperature.

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10

Franciolini, F., i W. Nonner. "A multi-ion permeation mechanism in neuronal background chloride channels." Journal of General Physiology 104, nr 4 (1.10.1994): 725–46. http://dx.doi.org/10.1085/jgp.104.4.725.

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Unitary current/voltage relationships of background Cl channels of rat hippocampal neurons were determined for varied gradients and absolute concentrations of NaCl. The channels revealed permeabilities for both Cl and Na ions. A hyperlinear increase of unitary conductance, observed for a symmetrical increase of salt concentration from 300 and 600 mM, indicated a multi-ion permeation mechanism. A variety of kinetic models of permeation were tested against the experimental current/voltage relationships. Models involving a pore occupied by mixed complexes of up to five ions were necessary to reproduce all measurements. A minimal model included four equilibrium states and four rate-limiting transitions, such that the empty pore accepts first an anion and then can acquire one or two cation/anion pairs. Three transport cycles are formed: a slow anion cycle (between the empty and single-anion states), a slow cation cycle (between the one- and three-ion states), and a fast anion cycle (between the three- and five-ion states). Thus, permeant anions are required for cation permeation, and several bound anions and cations promote a high rate of anion permeation. The optimized free-energy and electrical charge parameters yielded a self-consistent molecular interpretation, which can account for the particular order in which the pore accepts ions from the solutions. Although the model describes the mixed anion/cation permeability of the channel observed at elevated concentrations, it predicts a high selectivity for Cl anion at physiological ionic conditions.

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11

Liu, Xi. "Poly[tetramethylammonium [μ4-bromido-di-μ2-bromido-dicuprate(I)]]". Acta Crystallographica Section E Structure Reports Online 63, nr 11 (3.10.2007): m2651. http://dx.doi.org/10.1107/s1600536807047885.

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The title compound, {(C4H12N)[Cu2Br3]} n , consists of CuI-bromide complex anions and tetramethylammonium cations. The bromide ions bridge CuI ions to form one-dimensional polymeric chains. Both the cation and the anion have mirror symmetries; in the cation, the N atom and two C atoms are located on a mirror plane, while in the complex anion, the three bromide ions are located on two different mirror planes. No hydrogen bonding occurs in the crystal structure.

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12

Pritchard, J. B., i D. S. Miller. "Comparative insights into the mechanisms of renal organic anion and cation secretion". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 261, nr 6 (1.12.1991): R1329—R1340. http://dx.doi.org/10.1152/ajpregu.1991.261.6.r1329.

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Comparative models have played a major role in defining the mechanisms that enable vertebrate proximal tubules to transport organic anions and cations from the peritubular interstitium to the urine. The unique advantages of these models and their contributions to our understanding of organic anion and cation transport mechanisms are summarized here. Recent studies of the organic anion transport system suggest that transport is coupled to metabolic energy via indirect coupling to the sodium gradient. Organic anions enter the cell across the basolateral membrane in exchange for alpha-ketoglutarate (alpha-KG), and the alpha-KG is returned to the interior via Na-alpha-KG cotransport. Indirect coupling to Na has been demonstrated in both isolated membranes and intact renal epithelial cells of species ranging from marine crustaceans to mammals. This mechanism was shown to drive not only cellular accumulation but also secretory transepithelial fluxes of organic anions. Luminal exit of secreted organic anions appears to be carrier mediated but is, at present, poorly understood, with mediated potential-driven efflux and anion exchange-driven efflux implicated in some species. As for organic anions, the renal clearance of some organic cations approaches the renal plasma flow. Although there is considerable variation in the handling of specific substrates between species, the basic properties of organic cation transport include carrier-mediated potential-driven uptake at the basolateral membrane, intracellular sequestration that reduces the free concentration of the cation, and luminal exit by organic cation-proton exchange. Reabsorptive transport is also observed for some organic cations, but its mechanisms and driving forces are not well understood.

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13

Mirocki, Artur, i Artur Sikorski. "Structural Characterization of Multicomponent Crystals Formed from Diclofenac and Acridines". Materials 15, nr 4 (17.02.2022): 1518. http://dx.doi.org/10.3390/ma15041518.

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Multicomponent crystals containing diclofenac and acridine (1) and diclofenac and 6,9-diamino-2-ethoxyacridine (2) were synthesized and structurally characterized. The single-crystal XRD measurements showed that compound 1 crystallizes in the triclinic P-1 space group as a salt cocrystal with one acridinium cation, one diclofenac anion, and one diclofenac molecule in the asymmetric unit, whereas compound 2 crystallizes in the triclinic P-1 space group as an ethanol solvate monohydrate salt with one 6,9-diamino-2-ethoxyacridinium cation, one diclofenac anion, one ethanol molecule, and one water molecule in the asymmetric unit. In the crystals of the title compounds, diclofenac and acridines ions and solvent molecules interact via N–H⋯O, O–H⋯O, and C–H⋯O hydrogen bonds, as well as C–H⋯π and π–π interactions, and form heterotetramer bis[⋯cation⋯anion⋯] (1) or heterohexamer bis[⋯cation⋯ethanol⋯anion⋯] (2). Moreover, in the crystal of compound 1, acridine cations and diclofenac anions interact via N–H⋯O hydrogen bond, C–H⋯π and π–π interactions to produce blocks, while diclofenac molecules interact via C–Cl⋯π interactions to form columns. In the crystal of compound 2, the ethacridine cations interact via C–H⋯π and π–π interactions building blocks, while diclofenac anions interact via π–π interactions to form columns.

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14

Kazheva, Olga N., Enric Canadell, Grigorii G. Aleksandrov, Nataliya D. Kushch i Oleg A. Dyachenko. "Quasi-three-dimensional network of molecular interactions and electronic structure of a new organic semiconductor, ET(NCS)0.77". Acta Crystallographica Section B Structural Science 58, nr 1 (24.01.2001): 148–52. http://dx.doi.org/10.1107/s0108768101019322.

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The radical cation salt ET(NCS)0.77 [bis(ethylenedithio)tetrathiafulvalene thiocyanate (1/0.77)] has been prepared for the first time by electrocrystallization and its crystal and electronic structure at 110 K was investigated. The unit-cell dimensions are orthorhombic, a = 6.638 (1), b = 8.309 (2), c = 28.776 (6) Å, V = 1587.1 (6) Å3, space group Pbcm, Z = 4. The compound has a layered structure. The ET radical cations of the conducting cationic layer build stacks. In the anionic layer the thiocyanate groups form polymeric chains where they are oriented in a `head-to-tail' mode. The structure has short intermolecular contacts of the cation–cation, anion–anion and cation–anion types, which leads to the formation of a three-dimensional structure of intermolecular interactions. This phenomenon is very rare in molecular conductors. Tight binding band structure calculations suggest, however, that the interlayer interactions through the anions are weak and that the incomplete occupation of the anion sites is the reason for the activated conductivity of the salt.

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15

Anitha, R., S. Athimoolam, S. Asath Bahadur i M. Gunasekaran. "4-Chloroanilinium 3-carboxyprop-2-enoate". Acta Crystallographica Section E Structure Reports Online 68, nr 4 (3.03.2012): o959—o960. http://dx.doi.org/10.1107/s1600536812008458.

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In the title compound, C6H7ClN+·C4H3O4−, the cations and anions lie on mirror planes and hence only half of the molecules are present in the asymmeric unit. The 4-chloroanilinium cation and hydrogen maleate anion in the asymmetric unit are each planar and are oriented at an angle of 15.6 (1)° to one another and perpendicular to thebaxis. A characterestic intramolecular O—H...O hydrogen bond, forming an S(7) motif, is observed in the maleate anion. In the crystal, the cations and anions are linked by N—H...O hydrogen bonds, forming layers in theabplane. The aromatic rings of the cations are sandwiched between hydrogen-bonded chains and rings formed through the amine group of the cation and maleate anions, leading to alternate hydrophobic (z= 0 or 1) and hydrophilic layers (z= 1/2) along thecaxis.

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16

Çevik, Sabri, Musa Sarı, Murat Sarı i Tuncay Tunç. "Crystal structure of 4,4′-bipyridine-1,1'-diium naphthalene-2,6-disulfonate dihydrate". Acta Crystallographica Section E Structure Reports Online 70, nr 9 (9.08.2014): o989—o990. http://dx.doi.org/10.1107/s160053681401784x.

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The title hydrated molecular organic salt, C10H10N22+·C10H6O6S22−·2H2O, crystallized with half a bipyridinium cation, half a naphthalene-2,6-disulfonate anion and a water molecule in the asymmetric unit. The whole cation and anion are generated by inversion symmetry, the inversion centers being at the center of the bridging C—C bond of the cation, and at the center of the fused C—C bond of the naphthalene group of the anion. In the crystal, the anions and cations stack alternately along theaaxis with π–π interactions [inter-centroid distance = 3.491 (1) Å]. The anions are linkedviaO—H...O(sulfonate) hydrogen bonds involving two inversion-related water molecules, forming chains along [10-1]. These chains are bridged by bifurcated N—H...(O,O) hydrogen bonds, forming a three-dimensional framework structure. There are also C—H...O hydrogen bonds present, reinforcing the framework structure.

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17

Sivakumar, P., S. Israel i G. Chakkaravarthi. "Crystal structures of 2-methylpyridinium hydrogen 2,3-bis(4-methylbenzoyloxy)succinate and bis-[4-methylpyridinium hydrogen 2,3-bis(4-methylbenzoyloxy)succinate] pentahydrate". Acta Crystallographica Section E Crystallographic Communications 73, nr 10 (15.09.2017): 1483–87. http://dx.doi.org/10.1107/s2056989017012981.

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The title salt (I), C6H8N+·C20H17O8−, comprises a 2-methylpyridinium cation and a 2,3-bis(4-methylbenzoyloxy)succinate mono-anion while the salt (II), 2C6H8N+·2C20H17O8−·5H2O, consists of a pair of 4-methylpyridinium cations and 2,3-bis(4-methylbenzoyloxy)succinate mono-anions and five water molecules of solvation in the asymmetric unit. In (I), the dihedral angle between the aromatic rings of the anion is 40.41 (15)°, comparing with 43.0 (3) and 85.7 (2)° in the conformationally dissimilar anion molecules in (II). The pyridine ring of the cation in (I) is inclined at 23.64 (16) and 42.69 (17)° to the two benzene moieties of the anion. In (II), these comparative values are 4.7 (3), 43.5 (3)° and 43.5 (3), 73.1 (3)° for the two associated cation and anion pairs. The crystal packing of (I) is stabilized by inter-ionic N—H...O, O—H...O and C—H...O hydrogen bonds as well as weak C—H...π interactions, linking the ions into infinite chains along [100]. In the crystal packing of (II), the anions and cations are also linked by N—H...O and O—H...O hydrogen bonds involving also the water molecules, giving a two-dimensional network across (001). The crystal structure is also stabilized by weak C—H...O and C—H...π interactions.

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18

Grover, A. K., A. P. Singh, P. K. Rangachari i P. Nicholls. "Ion movements in membrane vesicles: a new fluorescence method and application to smooth muscle". American Journal of Physiology-Cell Physiology 248, nr 3 (1.03.1985): C372—C378. http://dx.doi.org/10.1152/ajpcell.1985.248.3.c372.

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A method is described for studying ion permeabilities of membrane vesicles based on the principle that when membrane permeability to H+ is very high, the H+ movement is determined by the membrane potential generated by the H+ movement. The rate of H+ movement under these conditions thus gives a measure of the rate of dissipation of this membrane potential by comovement of anions or countermovement of cations present. Thus, by studying the H+ efflux using an impermeant cation and different anions, the membrane permeability to the anions can be assessed. Similarly, the use of an impermeant anion allows the study of the permeation of various cations. H+ movement was followed across the membranes by monitoring a change in the fluorescence intensity of the pH-sensitive dye pyranine trapped inside the membranes. This method when tested using phosphatidylcholine liposomes yielded the expected results, i.e., permeability of the liposomal membrane was: Cl- greater than SO2-4 and K+ greater than Na+. A plasma membrane-enriched fraction loaded with pyranine was isolated from estrogen-dominant rat myometrium. The anion permeability characteristics of this membrane were studied using tetramethylammonium (TMA+) as the poorly permeant cation, and the cation permeability was studied using L-glutamate- as the poorly permeant anion. The anion permeabilities were D-glutamate- less than L-glutamate- less than glutarate2- less than Cl- less than or equal to SO2-4, and the cation permeabilities were TMA+ less than K+ less than Na+. It is hypothesized that the observed anomalously higher Na+ and SO2-4 movements may involve special mechanisms.

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Zeindlhofer, Veronika, Phillip Hudson, Ádám Márk Pálvölgyi, Matthias Welsch, Mazin Almarashi, H. Lee Woodcock, Bernard Brooks, Katharina Bica-Schröder i Christian Schröder. "Enantiomerization of Axially Chiral Biphenyls: Polarizable MD Simulations in Water and Butylmethylether". International Journal of Molecular Sciences 21, nr 17 (28.08.2020): 6222. http://dx.doi.org/10.3390/ijms21176222.

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In this study, we investigate the influence of chiral and achiral cations on the enantiomerization of biphenylic anions in n-butylmethylether and water. In addition to the impact of the cations and solvent molecules on the free energy profile of rotation, we also explore if chirality transfer between a chiral cation and the biphenylic anion is possible, i.e., if pairing with a chiral cation can energetically favour one conformer of the anion via diastereomeric complex formation. The quantum-mechanical calculations are accompanied by polarizable MD simulations using umbrella sampling to study the impact of solvents of different polarity in more detail. We also discuss how accurate polarizable force fields for biphenylic anions can be constructed from quantum-mechanical reference data.

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20

Wickramasinhage, Ravindra N., C. John McAdam, Lyall R. Hanton, Stephen C. Moratti i Jim Simpson. "The structure and Hirshfeld surface analysis of the salt 3-methacrylamido-N,N,N-trimethylpropan-1-aminium 2-acrylamido-2-methylpropane-1-sulfonate". Acta Crystallographica Section E Crystallographic Communications 75, nr 10 (10.09.2019): 1445–51. http://dx.doi.org/10.1107/s2056989019012003.

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The title salt, C10H21N2O+·C7H12NO4S−, comprises a 3-methacrylamido-N,N,N-trimethylpropan-1-aminium cation and a 2-acrylamido-2-methylpropane-1-sulfonate anion. The salt crystallizes with two unique cation–anion pairs in the asymmetric unit of the orthorhombic unit cell. The crystal studied was an inversion twin with a 0.52 (4):0.48 (4) domain ratio. In the crystal, the cations and anions stack along the b-axis direction and are linked by an extensive series of N—H...O and C—H...O hydrogen bonds, forming a three-dimensional network. Hirshfeld surface analysis was carried out on both the asymmetric unit and the two individual salts. The contribution of interatomic contacts to the surfaces of the individual cations and anions are also compared.

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21

Jordan, Matthew L., Tanmay Kulkarni, Dodangodage Ishara Senadheera, Revati Kumar, Yupo J. Lin i Christopher G. Arges. "Imidazolium-Type Anion Exchange Membranes for Improved Organic Acid Transport and Permselectivity in Electrodialysis". Journal of The Electrochemical Society 169, nr 4 (1.04.2022): 043511. http://dx.doi.org/10.1149/1945-7111/ac6448.

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Most commercial anion exchange membranes (AEMs) deploy quaternary ammonium moieties. Alternative cation moieties have been explored in AEMs for fuel cells, but there are no studies focused examining alternative tethered cations in AEMs for ionic separations—such as organic acid anion transport via electrodialysis. H-cell and conductivity experiments demonstrate that tethered benzyl 1-methyl imidazolium groups in polysulfone AEMs enhance lactate conductivity by 49% and improved lactate anion flux by 24x when compared to a quaternary benzyl ammonium polysulfone AEM. An electrodialysis demonstration with the imidazolium-type AEM showed a 2x improvement in lactate anion flux and 20% improvement in permselectivity when benchmarked against the quaternary ammonium AEM. Molecular dynamics and 2D NOESY NMR revealed closer binding of lactate anions to the imidazolium cations when compared to the quaternary ammonium cation. It is posited that this closer binding is responsible to greater flux values observed with imidazolium-type AEM.

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22

Cebollada, Andrea, Alba Vellé i Pablo J. Sanz Miguel. "Hirshfeld and DFT analysis of the N-heterocyclic carbene proligand methylenebis(N-butylimidazolium) as the acetonitrile-solvated diiodide salt". Acta Crystallographica Section C Structural Chemistry 72, nr 6 (5.05.2016): 456–59. http://dx.doi.org/10.1107/s2053229616006781.

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N-Heterocyclic carbene (NHC) based systems are usually exploited in the exploration of catalytic mechanisms and processes in organocatalysis, and homo- and heterogeneous catalysis. However, their molecular structures have not received adequate attention. The NHC proligand methylenebis(N-butylimidazolium) has been synthesized as the acetonitrile solvate of the diiodide salt, C15H26N42+·2I−·CH3CN [1,1′-methylenebis(3-butylimidazolium) diiodide acetonitrile monosolvate], and fully characterized. An interesting cation–anion connection pattern has been identified in the crystal lattice, in which three iodide anions interact simultaneously with thecisoid-oriented cation. A Hirshfeld surface analysis reveals the predominance of hydrogen bonding over anion–π interactions. This particular arrangement is observed in different methylene-bridged bis(imidazolium) cations bearing chloride or bromide counter-anions. Density functional theory (DFT) calculations with acetonitrile as solvent reproduce the geometry of the title cation.

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23

Gjikaj, Mimoza, Peng Wu i Niels-Patrick Pook. "Hexaaquanickel(II) dihydrogen hypodiphosphate". Acta Crystallographica Section E Structure Reports Online 69, nr 12 (13.11.2013): i83. http://dx.doi.org/10.1107/s1600536813030717.

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The asymmetric unit of the title compound, [Ni(H2O)6](H2P2O6), contains one-half of the hexaaquanickel(II) cation and one-half of the dihydrogen hypodiphosphate anion. In the complex cation, the Ni2+atom is located on an inversion center and has an octahedral coordination sphere. The P—P distance in the centrosymmetric anion is 2.1853 (7) Å. In the crystal, discrete [Ni(H2O)6]2+cations and (H2P2O6)2−anions are stacked in columns parallel to thecaxis and are linked into a three-dimensional network by medium-strength O—H...O hydrogen bonds.

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24

Srinivas, Dharavath, Vikas D. Ghule i Krishnamurthi Muralidharan. "Energetic salts prepared from phenolate derivatives". New J. Chem. 38, nr 8 (2014): 3699–707. http://dx.doi.org/10.1039/c4nj00533c.

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Kennedy, Alan R., i Maurice O. Okoth. "2-Aminoethanaminium iodide". Acta Crystallographica Section E Structure Reports Online 68, nr 6 (16.05.2012): o1731. http://dx.doi.org/10.1107/s160053681202065x.

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The title salt, [NH3CH2CH2NH2]+·I−, has an array structure based on strong intermolecular N—H...N hydrogen bonding formed between the ammonium and amine groups of adjacent cations. This interaction gives a helical chain of cations that runs parallel to the b axis. The four remaining NH group H atoms all form hydrogen bonds to the iodide anion, and these iodide anions lie in channels parallel to the cation–cation chains.

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26

Xu, Qian. "Bis(2-methylpiperidinium) naphthalene-1,5-disulfonate". Acta Crystallographica Section E Structure Reports Online 68, nr 6 (16.05.2012): o1733. http://dx.doi.org/10.1107/s1600536812020041.

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In the structure of the title molecular salt, 2C6H14N+·C10H6O6S2 2−, the asymmetric unit consists of one 2-methylpiperidinium cation and one-half of a naphthalene-1,5-disulfonate anion; the anion lies across a centre of symmetry. In the crystal, the cations and anions are linked through N—H...O hydrogen bonds, forming a two-dimensional network.

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27

Kaduk, James A., Nicholas C. Boaz, Emma L. Markun, Amy M. Gindhart i Thomas N. Blanton. "Crystal structure of osimertinib mesylate Form B (Tagrisso), (C₂₈H₃₄N₇O₂)(CH₃O₃S)". Powder Diffraction 36, nr 4 (19.10.2021): 282–90. http://dx.doi.org/10.1017/s0885715621000555.

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The crystal structure of osimertinib mesylate Form B has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional techniques. Osimertinib mesylate Form B crystallizes in space group P-1 (#2) with a = 11.42912(17), b = 11.72274(24), c = 13.32213(22) Å, α = 69.0265(5), β = 74.5914(4), γ = 66.4007(4)°, V = 1511.557(12) Å3, and Z = 2. The crystal structure is characterized by alternating layers of cation–anion and parallel stacking interactions parallel to the ab-planes. The cation is protonated at the nitrogen atom of the dimethylamino group, which forms a strong hydrogen bond between the cation and the anion. That hydrogen atom also participates in a weaker intramolecular hydrogen bond to an amino nitrogen. There are two additional N–H⋅⋅⋅O hydrogen bonds between the cation and the anion. Several C–H⋅⋅⋅O hydrogen bonds also link the cations and anions. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™.

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28

Sarr, Modou, Carina Merkens, Aminata Diassé-Sarr, Libasse Diop i Ulli Englert. "Bis(cyclohexylammonium) tetrachloridodiphenylstannate(IV)". Acta Crystallographica Section E Structure Reports Online 70, nr 6 (17.05.2014): m220—m221. http://dx.doi.org/10.1107/s160053681401109x.

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The title compound, (C6H14N)2[Sn(C6H5)2Cl4], contains cyclohexylammonium cations in general positions and a stannate(IV) anion that is located on a twofold rotation axis. The SnIVatom in the complex anion is surrounded by four Cl−ligands and twotrans-phenyl groups in a distorted octahedral configuration. The anions are connected with the cations through N—H...Cl hydrogen bonds. Every cation is involved in three N—H...Cl bonds to the chloride ligands of three different anions, and each chloride ligand is linked to two cations. This arrangement leads to a layered structure parallel to (010).

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29

Ndiolene, Adrienne, Tidiane Diop, Mouhamadou Sembène Boye, Aminata Diasse-Sarr i Ulli Englert. "A new organic–inorganic compound, ethylenediammonium hexachloridostannate(IV) p-anisaldehyde disolvate". Acta Crystallographica Section E Crystallographic Communications 77, nr 7 (8.06.2021): 696–99. http://dx.doi.org/10.1107/s205698902100579x.

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The asymmetric unit of the title organic–inorganic hybrid complex [systematic name: ethane-1,2-diaminium hexachloridostannate(IV)–4-methoxybenzaldehyde (1/2)], (C2H10N2)[SnCl6]·2C8H8O2, contains one half of an ethylenediammonium cation, one half of an [SnCl6]2− anion and one p-anisaldehyde molecule. Both the organic cation and the quasi-regular octahedral inorganic anion are located about inversion centres. The organic cations and [SnCl6]2− anions lie in layers parallel to the ac plane with p-anisaldehyde molecules occupying the space between the layers. A network of classical N—H...Cl and N—H...O hydrogen bonds exists between the ethylenediammonium cations and the [SnCl6]2− anions and p-anisaldehyde molecules. These interactions, together with non-classical C—H...O interactions between the ethylenediammonium cations and the p-anisaldehyde molecules, serve to hold the structure together. The crystal studied was refined as a two-component twin.

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30

Han, Qiuxia, i Jie Li. "4-(4-Aminophenoxy)anilinium 2-hydroxy-2,2-diphenylacetate". Acta Crystallographica Section E Structure Reports Online 63, nr 11 (24.10.2007): o4380. http://dx.doi.org/10.1107/s1600536807051057.

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The asymmetric unit of the title salt, C12H13N2O+·C14H11O3 −, contains two cations and two anions, in which cation–anion pairs are linked together by an N—H...O hydrogen bond. An intramolecular O—H...O hydrogen bond occurs within each anion and forms an S(5) ring. These component ions are organized through further hydrogen bonds into layers parallel to (001).

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31

Gueye, Ndongo, Libasse Diop, Kieran C. Molloy i Gabrielle Kociok-Köhn. "Dibenzylazanium (oxalato-κ2 O,O′)triphenylstannate(IV)". Acta Crystallographica Section E Structure Reports Online 68, nr 6 (31.05.2012): m854—m855. http://dx.doi.org/10.1107/s1600536812021125.

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The title compound, (C14H16N)[Sn(C6H5)3(C2O2)], was synthesised by allowing C2O4(Bz2NH2)2 (Bz = benzyl) to react with SnPh3Cl. The asymmetric unit is built up by four SnPh3C2O4 anions and four Bz2NH2 cations which are related by a pseudo-inversion centre. Each SnIV cation is five-coordinated by the three phenyl groups and two O atoms belonging to the chelating oxalate ligand; the coordination geometry is that of a distorted trigonal bipyramid. Anions and cations are linked through N—H...O hydrogen bonds into a layer structure parallel to (001). Moreover, the anion–cation pairs are associated by two bifurcated N—H...O hydrogen bonds, generating pseudo-dimers. One of the phenyl groups of one anion is disordered over two sets of sites in a 0.69:0.31 ratio. The Flack parameter value of 0.44 (1) indicates racemic twinning.

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32

Burckhardt, Gerhard, i Natascha A. Wolff. "Structure of renal organic anion and cation transporters". American Journal of Physiology-Renal Physiology 278, nr 6 (1.06.2000): F853—F866. http://dx.doi.org/10.1152/ajprenal.2000.278.6.f853.

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Here we review the structural and functional properties of organic anion transporters (OAT1, OAT2, OAT3) and organic cation transporters (OCTN1, OCTN2, OCT1, OCT2, OCT3), some of which are involved in renal proximal tubular organic anion and cation secretion. These transporters share a predicted 12-transmembrane domain (TMD) structure with a large extracellular loop between TMD1 and TMD2, carrying potential N-glycosylation sites. Conserved amino acid motifs revealed a relationship to the sugar transporter family within the major facilitator superfamily. Following heterologous expression, most OATs transported the model anion p-aminohippurate (PAH). OAT1, but not OAT2, exhibited PAH-α-ketoglutarate exchange. OCT1–3 transported the model cations tetraethylammonium (TEA), N1-methylnicotinamide, and 1-methyl-4-phenylpyridinium. OCTNs exhibited transport of TEA and/or preferably the zwitterionic carnitine. Substrate substitution as well as cis-inhibition experiments demonstrated polyspecificity of the OATs, OCTs, and OCTN1. On the basis of comparison of the structurally closely related OATs and OCTs, it may be possible to delineate the binding sites for organic anions and cations in future experiments.

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33

Nguyen, Vu D., Cameron A. McCormick, Robert A. Pascal, Joel T. Mague i Lynn V. Koplitz. "Crystal structure of 2-cyano-1-methylpyridinium bromide". Acta Crystallographica Section E Crystallographic Communications 71, nr 11 (17.10.2015): o854—o855. http://dx.doi.org/10.1107/s2056989015019167.

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In the title molecular salt, C7H7N2+·Br−, all the non-H atoms lie on crystallographic mirror planes. The packing consists of (010) cation–anion layers, with the cations forming dimeric unitsviavery weak pairwise C—H...N interactions. Weak C—H...Br interactions link the cations to the anions.

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34

Tschauner, Oliver. "Pressure-Dependent Crystal Radii". Solids 4, nr 3 (28.08.2023): 235–53. http://dx.doi.org/10.3390/solids4030015.

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This article reports the pressure-dependent crystal radii of Mg, Si, Ge, Be, Fe, Ca, Sr, Ba, Al, Ti, Li, Na, K, Cs, and of some rare earths, that is: the major Earth mantle elements, important minor, and some trace elements. Pressure dependencies of O2−, Cl−, and Br− are also reported. It is shown that all examined cation radii vary linearly with pressure. Cation radii obey strict correlations between ionic compressibilities and reference 0 GPa radii, thus reducing previous empirical rules of the influence of valence, ion size, and coordination to a simple formula. Both cation and anion radii are functions of nuclear charge number and a screening function which for anions varies with pressure, and for cations is pressure-independent. The pressure derivative of cation radii and of the anion radii at high pressure depends on electronegativity with power −1.76.

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35

John, Andreas, i Hans Bock. "Elektronentransfer und Kontaktionen-Bildung, 42 [1,2] Cyclovoltammetrische und ESR / ENDOR-Untersuchungen der Einelektronen-Reduktion von Diphenochinonen / Electron Transfer and Contact Ion Pair Formation, 42 [1,2] Cyclovoltammetric and ESR / ENDOR Investigations of the One-Electron Reduction of Diphenoquinones". Zeitschrift für Naturforschung B 50, nr 11 (1.11.1995): 1699–716. http://dx.doi.org/10.1515/znb-1995-1118.

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Semiquinone radical anions are prototype compounds for contact ion pair formation with metal counter cations. In order to investigate the still open question whether bulky alkyl groups can sterically interfere, diphenoquinone derivatives O=C(RC=CH)2C=C(HC=CR)2C=O with R = C(CH3)3, CH(CH3)2 and CH3 have been selected and the following ESR/ENDOR results are obtained for the alkaline metal cations: The tetrakis(tert-butyl)-substituted radical anion only adds Li⊕ and Na⊕, while K⊕ forms no ion pair. The 3,3ʹ,5,5ʹ-tetra(isopropyl)diphenoquinone radical anion is accessible to all cations Me⊕, although Rb⊕ and Cs⊕ seem to be present solvent-separated in solution. The tetramethyl-substituted radical anion unfortunately polymerizes rapidly. Additional information concerns the ESR/ENDOR proof for ion triple radical cation formation [Li⊕ M•⊖Li⊕]•⊕, or the difference in the coupling constants upon Me⊕ docking at one δ⊖O=C group, suggesting that about 87% of the spin density is located in the cation-free molecular half of the diphenoquinone radical anion. Based on the wealth of ESR/ENDOR information, crystallization of the contact ion pairs and their structural characterization should be attempted.

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36

Xu, Jian-Fu, Ping Chen, Rubin Zhuang, Chang-Cang Huang i Han-Hui Zhang. "catena-Poly[1,2-ethylenediammonium [[nitratouranyl]-μ3-phosphito] dihydrate]". Acta Crystallographica Section E Structure Reports Online 62, nr 4 (15.03.2006): m763—m764. http://dx.doi.org/10.1107/s1600536806008476.

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The crystal structure of the title compound, {(C2H10N2)[U(HPO3)(NO3)O2]·2H2O} n , consists of polymeric uranyl complex anions, ethylenediammonium cations and uncoordinated water molecules. The polymeric uranyl complex anion displays a ladder-like structure, each UO2 unit being coordinated by three phosphite dianions and one nitrate anion with a pentagonal–bipyramidal geometry. The ethylenediammonium cation is located on an inversion center and is hydrogen bonded with the uranyl complex.

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37

Miller, D. S., P. M. Smith i J. B. Pritchard. "Organic anion and cation transport in crab urinary bladder". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 257, nr 3 (1.09.1989): R501—R505. http://dx.doi.org/10.1152/ajpregu.1989.257.3.r501.

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Crab urinary bladder, a simple, flat-sheet epithelium, is structurally and functionally analogous to vertebrate renal proximal tubule. Like proximal tubule, crab bladder plays an important role in the excretion of potentially toxic, charged metabolites and xenobiotics. Bladders from Cancer borealis secrete monovalent, organic anions and cations in vivo and in vitro. For organic cations, secretion is a two-step process, with mediated and energetically downhill uptake into cells at the serosal membrane and uphill exit at the luminal membrane. The uptake step may be driven by the electrical potential difference across the serosal membrane, the luminal step by organic cation-proton exchange. Monovalent organic anions are also secreted by a separate two-step process. Recent experiments with intact bladder tissue and isolated membrane vesicles show that (as in mammalian proximal tubule) uphill serosal uptake can be coupled indirectly to the Na+ gradient. Organic anion (p-aminohippurate; PAH) uptake is driven by exchange for certain divalent organic anions, e.g., glutarate and alpha-ketoglutarate. The divalent anion gradient (in greater than out) is in turn maintained by Na+-coupled divalent uptake. The PAH exist step at the luminal membrane is mediated and downhill; it may involve anion exchange.

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38

Raghavendra Kumar, P., Upereti Shailesh i B. S. Palakshamurthy. "Crystal structure of (2-chloroethyl)[2-(methylsulfanyl)benzyl]ammonium chloride". Acta Crystallographica Section E Crystallographic Communications 71, nr 6 (13.05.2015): 621–23. http://dx.doi.org/10.1107/s2056989015008221.

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In the title molecular salt, C10H15ClNS+·Cl−, the cation is [R′R"NH2]+, whereR′ is 2-MeS-C6H4CH2– andR" is –CH2CH2Cl, and the anion is Cl−. In the cation, the N atom is protonated withsp3-hybridization and with a tetrahedral geometry. In the crystal, the anions are connected to the cations through two pairs of N—H...Cl hydrogen bonds, generating a four-centred inversion dimer with anR42(8) ring motif.

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39

Kaduk, James A., Amy M. Gindhart i Thomas N. Blanton. "Crystal structure of hyoscyamine sulfate monohydrate, (C17H24NO3)2(SO4)(H2O)". Powder Diffraction 35, nr 4 (3.11.2020): 286–92. http://dx.doi.org/10.1017/s0885715620000603.

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The crystal structure of hyoscyamine sulfate monohydrate has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional techniques. Hyoscyamine sulfate monohydrate crystallizes in space group P21 (#4) with a = 6.60196(2), b = 12.95496(3), c = 20.93090(8) Å, β = 94.8839(2)°, V = 1783.680(5) Å3, and Z = 2. Despite the traditional description as a dihydrate, hyoscyamine sulfate crystallizes as a monohydrate. The two independent hyoscyamine cations have different conformations, which have similar energies. One of the cations is close to the minimum-energy conformation. Each of the protonated nitrogen atoms in the cations acts as a donor to the sulfate anion. The hydroxyl group of one cation acts as a donor to the sulfate anion, while the hydroxyl group of the other cation acts as a donor to the water molecule. The water molecule acts as a donor to two different sulfate anions. The cations and anions are linked by complex chains of hydrogen bonds along the a-axis. The powder pattern has been submitted for inclusion in the Powder Diffraction File™ (PDF®).

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40

Li, Zhi-Feng, Yi-Chao Zhang, Xiao-Qin Hu i Chun-Xiang Wang. "Crystal structure of poly[μ6-adipato-diaquadi-μ2-oxalato-didysprosium(III)]". Acta Crystallographica Section E Structure Reports Online 70, nr 12 (15.11.2014): m399—m400. http://dx.doi.org/10.1107/s1600536814024544.

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In the title coordination polymer, [Dy2(C6H8O4)(C2O4)2(H2O)2]n, the asymmetric unit consists of one Dy3+cation, one half of an adipate anion, two halves of oxalate anions and one coordinating water molecule. The adipate and oxalate ions are located on centres of inversion. The Dy3+cation has a distorted tricapped trigonal–prismatic geometry and is coordinated by nine O atoms, four belonging to three adipate anions, four to two oxalate anions and one from an aqua ligand. The cations are bridged by adipate ligands, generating a two-dimensional network parallel to (010). This network is further extended into three dimensions by coordination of the rigid oxalate ligands and is further consolidated by O—H...O hydrogen bonds. A part of the adipate anion is disordered over two positions in a 0.75:0.25 ratio.

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41

Wachter, Erin, Edith C. Glazer, Sean Parkin i Carolyn Pratt Brock. "An exceptional 5:4 enantiomeric structure". Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 72, nr 2 (1.04.2016): 223–31. http://dx.doi.org/10.1107/s205252061600127x.

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The only crystals that could be grown from racemic solutions of the PF6−salt of the resolvable cation [Ru(2,9-dimethyl-1,10-phenanthroline)2(dipyrido[3,2-d:2′,3′-f]quinoxaline)]2+have translational symmetry only (space groupP1), contain nine independent sets of ions, and include numerous independent solvent molecules (11 acetone, one diethyl ether and possibly several water molecules). Layers of hydrophobic cations alternate with layers containing most of the anions and solvent molecules. All nine cations have the same basic conformation, which is distorted by the presence of the methyl substituents on the two 1,10-phenanthroline ligands. Four pairs of enantiomeric cations within a layer are related by approximate inversion centers; the ninth cation, which shows no sign of disorder, makes the layer chiral. Within the cation layers stripes parallel to [110] of six cations alternate with stripes of three; the local symmetry and the cation orientations are different in the two stripes. These stripes are reflected in the organization of the anion/solvent layer. Theca80:20 inversion twinning found indicates that enantiomeric preference is transmitted less perfectly across the anion/solvent layer than within the cation layer. The structure is exceptional in having nine independent formula units and an unbalanced set (ratio 4:5) of resolvable enantiomers. The difficulty in growing crystals of this material is consistent with its structural complexity.

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42

Zeng, Ming-Hua, Li-Hong Zhu, Hong Liang i Seik Weng Ng. "Tetraaquabis(3-pyridinecarboxamide-κN)copper(II) bis(2,4,6-trinitrophenolate)". Acta Crystallographica Section E Structure Reports Online 62, nr 4 (22.03.2006): m822—m823. http://dx.doi.org/10.1107/s1600536806009500.

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The Cu atom in the title compound, [Cu(C6H6N2O)2(H2O)4](C6H2N3O7)2, exists in an all trans-O4N2Cu octahedron; the anion interacts indirectly with the cation through the coordinated water molecules. Hydrogen bonds link the cations and anions into a three-dimensional network.

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43

Xu, Qian. "Bis(3-methylpiperidinium) naphthalene-1,5-disulfonate". Acta Crystallographica Section E Structure Reports Online 68, nr 6 (12.05.2012): o1687. http://dx.doi.org/10.1107/s160053681202003x.

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The asymmetric unit of the title compound, 2C6H14N+·C10H6O6S2 2−, contains one 3-methylpiperidinium cation and one-half of the centrosymmetric naphthalene-1,5-disulfonate anion. In the crystal, anions and cations are linked through N—H...O hydrogen bonds into layers parallel to (101).

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44

Soecipto, Aristyo, Lawrence W. Y. Wong, Herman H. Y. Sung i Ian D. Williams. "Chiral anionic layers in tartramide spiroborate salts and variable solvation for [NR 4][B(TarNH2)2] (R = Et, Pr or Bu)". Acta Crystallographica Section C Structural Chemistry 76, nr 7 (30.06.2020): 695–705. http://dx.doi.org/10.1107/s2053229620008384.

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The spiroborate anion, namely, 2,3,7,8-tetracarboxamido-1,4,6,9-tetraoxa-5λ4-boraspiro[4.4]nonane, [B(TarNH2)2]−, derived from the diol L-tartramide TarNH2, [CH(O)(CONH2)]2, shows a novel self-assembly into two-dimensional (2D) layer structures in its salts with alkylammonium cations, [NR 4]+ (R = Et, Pr and Bu), and sparteinium, [HSpa]+, in which the cations and anions are segregated. The structures of four such salts are reported, namely, the tetrapropylazanium salt, C12H28N+·C8H12BN4O8 −, the tetraethylazanium salt hydrate, C8H20N+·C8H12BN4O8 −·6.375H2O, the tetrabutylazanium salt as the ethanol monosolvate hemihydrate, C16H36N+·C8H12BN4O8 −·C2H5OH·0.5H2O, and the sparteinium (7-aza-15-azoniatetracyclo[7.7.1.02,7.010,15]heptadecane) salt as the ethanol monosolvate, C15H27N2 +·C8H12BN4O8 −·C2H5OH. The 2D anion layers have preserved intermolecular hydrogen bonding between the amide groups and a typical metric repeat of around 10 × 15 Å. The constraint of matching the interfacial area organizes the cations into quite different solvated arrangements, i.e. the [NEt4] salt is highly hydrated with around 6.5H2O per cation, the [NPr4] salt apparently has a good metric match to the anion layer and is unsolvated, whilst the [NBu4] salt is intermediate and has EtOH and H2O in its cation layer, which is similar to the arrangement for the chiral [HSpa]+ cation. This family of salts shows highly organized chiral space and offers potential for the resolution of both chiral cations and neutral chiral solvent molecules.

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45

Malathy, Sevaiyan, Jeyaraman Selvaraj Nirmalram i Packianathan Thomas Muthiah. "Crystal structure of 4-[(5-methylisoxazol-3-yl)aminosulfonyl]anilinium 3,5-dinitrosalicylate". Acta Crystallographica Section E Crystallographic Communications 71, nr 6 (13.05.2015): 618–20. http://dx.doi.org/10.1107/s2056989015008701.

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The title molecular salt, C10H12N3O3S+·C7H3N2O7−, protonation occurs at the amino N atom attached to the benzene ring of sulfamethoxazole. In the anion, there is an intramolecular O—H...O hydrogen bond and the cation is linked to the anion by an N—H...O hydrogen bond. In the extended structure, the cations and anions are linkedviaN—H...O, N—H...N and C—H...O hydrogen bonds, forming a three-dimensional framework.

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46

Rayes, Ali, Ahlem Dadi, Najla Mahbouli Rhouma, Francesco Mezzadri i Gianluca Calestani. "Synthesis and crystal structure of 4-fluorobenzylammonium dihydrogen phosphate, [FC6H4CH2NH3]H2PO4". Acta Crystallographica Section E Crystallographic Communications 72, nr 12 (15.11.2016): 1812–15. http://dx.doi.org/10.1107/s2056989016018090.

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The asymmetric unit of the title salt, [p-FC6H4CH2NH3]+·H2PO4−, contains one 4-fluorobenzylammonium cation and one dihydrogen phosphate anion. In the crystal, the H2PO4−anions are linked by O—H...O hydrogen bonds to build corrugated layers extending parallel to theabplane. The FC6H4CH2NH3+cations lie between these anionic layers to maximize the electrostatic interactions and are linked to the H2PO4−anions through N—H...O hydrogen bonds, forming a three-dimensional supramolecular network. Two hydrogen atoms belonging to the dihydrogen phosphate anion are statistically occupied due to disorder along the OH...HO direction.

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47

Zhang, Ke, Da-Dong Liang, Ming-Hui Wang, Yan Liu i Guo-You Luan. "Bis[tris(2,2′-bipyridyl-κ2N,N′)cobalt(II)]cyclo-tetravanadate undecahydrate". Acta Crystallographica Section C Crystal Structure Communications 69, nr 2 (26.01.2013): 138–41. http://dx.doi.org/10.1107/s0108270112051244.

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The title compound, [Co(C10H8N2)3]2[V4O12]·11H2O, is composed of two symmetry-related cations containing octahedrally coordinated CoIIions, a centrosymmetric [V4O12]4−anion with an eight-membered ring structure made up of four VO4tetrahedra, and 11 solvent water molecules. The CoIIcations and vanadate anions are isolated and build cation and anion layers, respectively. In addition, the title compound exhibits a three-dimensional network through intra- and intermolecular hydrogen-bond interactions between water molecules and O atoms of the anions, and the crystal structure is stabilized mainly by hydrogen bonds.

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Kaduk, James A., Amy M. Gindhart i Thomas N. Blanton. "Crystal structure of palbociclib isethionate Form B, (C24H30N7O2)(C2H5O4S)". Powder Diffraction 36, nr 3 (18.06.2021): 196–201. http://dx.doi.org/10.1017/s0885715621000361.

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The crystal structure of palbociclib isethionate has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional theory techniques. Palbociclib isethionate crystallizes in space group P-1 (#2) with a = 8.71334(4), b = 9.32119(6), c = 17.73725(18) Å, α = 80.0260(5), β = 82.3579(3), γ = 76.1561(1)°, V = 1371.282(4) Å3, and Z = 2. The crystal structure is dominated by cation⋯anion and cation⋯cation hydrogen bonds, which result in layers roughly parallel to the (104) plane. Both hydrogen atoms on the protonated nitrogen atom of the pyrimidine ring participate in strong hydrogen bonds to the anions. One proton binds to the sulfonate group, while the other bonds to the hydroxyl group of the isethionate anion. The hydroxyl group of the anion acts as a donor to a ketone oxygen atom in the cation. There are also strong N–H⋯N hydrogen bonds, which occur in pairs linking the cations into dimers with rings having a graph set R2,2(8). The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™.

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Diop, Mouhamadou Birame, Libasse Diop i Thierry Maris. "Crystal structures of the two salts 2-methyl-1H-imidazol-3-ium nitrate–2-methyl-1H-imidazole (1/1) and 2-methyl-1H-imidazol-3-ium nitrate". Acta Crystallographica Section E Crystallographic Communications 72, nr 4 (11.03.2016): 482–85. http://dx.doi.org/10.1107/s2056989016003789.

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The title salts, C4H7N2+·NO3−·C4H6N2, (I), and C4H7N2+·NO3−, (II), were obtained from solutions containing 2-methylimidazole and nitric acid in different concentrations. In the crystal structure of salt (I), one of the –NH H atoms of the imidazole ring shows half-occupancy, hence only every second molecule is in its cationic form. The nitrate anion in this structure lies on a twofold rotation axis. The neutral 2-methylimidazole molecule and the 2-methyl-1H-imidazol-3-ium cation interact through N—H...N hydrogen bonds to form [(C4H6N2)...(C4H7N2)+] pairs. These pairs are linked with two nitrate anions on both sides through bifurcated N—H...(O,O) hydrogen bonds into chains running parallel to [001]. In the crystal structure of salt (II), the C4H7N2+cation and the NO3−anion are both located on a mirror plane, leading to a statistical disorder of the methyl H atoms. The cations and anions again interact through bifurcated N—H...(O,O) hydrogen bonds, giving rise to the formation of chains consisting of alternating anions and cations parallel to [100].

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Kim, Hee-Joon. "Assembly of Sn(IV)-Porphyrin Cation Exhibiting Supramolecular Interactions of Anion···Anion and Anion···π Systems". Molbank 2022, nr 4 (25.09.2022): M1454. http://dx.doi.org/10.3390/m1454.

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Trans-diaqua[meso-tetrakis(4-pyridyl)porphyrinato]Sn(IV) dinitrate complexes were assembled in a two-dimensional manner via hydrogen bonding between aqua ligands and pyridyl substituents. Interestingly, this supramolecular assembly was accompanied by unconventional noncovalent interactions, such as anion···anion and anion···π interactions, which were confirmed by X-ray crystallographic analysis. Two nitrate anions close to 2.070 Å were constrained in a confined space surrounded by four hydrogen-bonded Sn(IV)-porphyrin cations. The nitrate anion was also 3.433 Å away from the adjacent pyrrole ring, and the dihedral angle between the two mean planes was estimated to be 7.39°. The preference of the anion···π interaction was related to the electron-deficient π-system owing to the high-valent Sn(IV) center and cationic nature of the porphyrin complex. These two unconventional noncovalent interactions played an important role in the formation of a one-dimensional array with pairs of Sn(IV)-porphyrin cation and nitrate anion.

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