Journal articles: 'Architecture, n.e.c'

1

Tamilvendan, Dhanapal, Ganesan Venkatesa Prabhu, Frank R. Fronczek, and Nagarajan Vembu. "N,N′-(Phenyliminodimethylene)diprop-2-enamide hemihydrate." Acta Crystallographica Section E Structure Reports Online 65, no. 6 (May 20, 2009): o1343. http://dx.doi.org/10.1107/s1600536809017784.

Full text

Abstract:

In the title compound, C14H17N3O2·0.5H2O, the asymmetric unit consists of anN,N′-(phenyliminodimethylene)diprop-2-enamide molecule and one half-molecule of water, with the O atom of the latter having 2 site symmetry. The supramolecular architecture is framed by the interplay of two-dimensional networks of both O—H...O and N—H...O interactions supported by C—H...O and edge-to-face C—H...π interactions.

APA, Harvard, Vancouver, ISO, and other styles

2

Asiri, Abdullah M., Hassan M. Faidallah, Khalid A. Khan, Seik Weng Ng, and Edward R. T. Tiekink. "N,N′-Bis[(E)-1-(thiophen-3-yl)ethylidene]ethane-1,2-diamine." Acta Crystallographica Section E Structure Reports Online 68, no. 4 (March 10, 2012): o1026. http://dx.doi.org/10.1107/s1600536812009798.

Full text

Abstract:

The complete molecule of the title compound, C14H16N2S2, is generated by a crystallographic inversion centre. The thiophene residue is close to being coplanar with the imine group [C—C—C—N torsion angle = 6.5 (2)°], and the conformation about the imine C=N bond [1.281 (2) Å] isE. In the crystal, the three-dimensional architecture is consolidated by C—H...N, C—H...π and S...S [3.3932 (7) Å] interactions.

APA, Harvard, Vancouver, ISO, and other styles

3

Shakuntala, K., S. Naveen, N. K. Lokanath, and P. A. Suchetan. "Crystal structures of isomeric 3,5-dichloro-N-(2,3-dimethylphenyl)benzenesulfonamide, 3,5-dichloro-N-(2,6-dimethylphenyl)benzenesulfonamide and 3,5-dichloro-N-(3,5-dimethylphenyl)benzenesulfonamide." Acta Crystallographica Section E Crystallographic Communications 73, no. 5 (April 11, 2017): 673–77. http://dx.doi.org/10.1107/s2056989017005230.

Full text

Abstract:

The crystal structures of three isomeric compounds of formula C14H13Cl2NO2S, namely 3,5-dichloro-N-(2,3-dimethylphenyl)-benzenesulfonamide (I), 3,5-dichloro-N-(2,6-dimethylphenyl)benzenesulfonamide (II) and 3,5-dichloro-N-(3,5-dimethylphenyl)benzenesulfonamide (III) are described. The molecules of all the three compounds are U-shaped with the two aromatic rings inclined at 41.3 (6)° in (I), 42.1 (2)° in (II) and 54.4 (3)° in (III). The molecular conformation of (II) is stabilized by intramolecular C—H...O hydrogen bonds and C—H...π interactions. The crystal structure of (I) features N—H...O hydrogen-bondedR22(8) loops interconnectedvia C(7) chains of C—H...O interactions, forming a three-dimensional architecture. The structure also features π–π interactions [Cg...Cg= 3.6970 (14) Å]. In (II), N—H...O hydrogen-bondedR22(8) loops are interconnectedviaπ–π interactions [intercentroid distance = 3.606 (3) Å] to form a one-dimensional architecture running parallel to theaaxis. In (III), adjacentC(4) chains of N—H...O hydrogen-bonded molecules running parallel to [010] are connectedviaC—H...π interactions, forming sheets parallel to theabplane. Neighbouring sheets are linkedviaoffset π–π interactions [intercentroid distance = 3.8303 (16) Å] to form a three-dimensional architecture.

APA, Harvard, Vancouver, ISO, and other styles

4

González-González, Juan Saulo, Nancy Evelyn Magaña-Vergara, Efrén Venancio García-Báez, Itzia Irene Padilla-Martínez, Juan Pablo Mojica-Sánchez, and Francisco Javier Martínez-Martínez. "Crystal Structure and Supramolecular Architecture of Antiallergic Diphenylene Diethyl Dioxalamates." Crystals 10, no. 11 (November 18, 2020): 1048. http://dx.doi.org/10.3390/cryst10111048.

Full text

Abstract:

The crystal structure and the supramolecular architectures of the antiallergic compounds N,N′-(4,4′-methanediyl-di-phenyl)-bis-diethyl dioxalamate (1); N′,N′-(4,4′-oxydi-p-phenylene)-bis-diethyl dioxalamate (2); N,N′-(4,4′-biphenylene)-bis- diethyl dioxalamate (3) are reported. The supramolecular self-assembly in 1-3 is driven by N-H···O=C hydrogen bonds and reinforced by C-H···O=C, C-H···π and C=O···C=O interactions. The three compounds preferred to form cross-linked supramolecular architectures. Intermolecular interactions also were studied by the Hirshfeld surface analysis, revealing that the H···H, O···H, and C···H are the more dominant contacts in the three compounds. The knowledge of crystal structure will allow us to perform theoretical studies to evaluate the antiallergic activity of compounds 1-3.

APA, Harvard, Vancouver, ISO, and other styles

5

Wu, Ya-Ming. "N-[5-(Diphenylphosphorylmethyl)-4-(4-fluorophenyl)-6-isopropylpyrimidin-2-yl]-N-methylmethanesulfonamide." Acta Crystallographica Section E Structure Reports Online 69, no. 11 (October 19, 2013): o1673. http://dx.doi.org/10.1107/s1600536813028286.

Full text

Abstract:

In the title compound, C28H29FN3O3PS, the pyrimidine ring is oriented at a dihedral angle of 50.9 (2)° with respect to the florobenzene ring, while the two phenyl rings bonding to the same P atom are twisted with respect to each other, making a dihedral angle of 62.2 (2)°. In the crystal, molecules are linked by weak C—H...O and C—H...F hydrogen bonds into a three-dimensional supramolecular architecture.

APA, Harvard, Vancouver, ISO, and other styles

6

Tayamon, Shahedeh, Thahira Begum S. A. Ravoof, Mohamed Ibrahim Mohamed Tahir, Karen A. Crouse, and Edward R. T. Tiekink. "N′-[Bis(benzylsulfanyl)methylidene]benzohydrazide." Acta Crystallographica Section E Structure Reports Online 68, no. 6 (May 5, 2012): o1640—o1641. http://dx.doi.org/10.1107/s1600536812019472.

Full text

Abstract:

In the title hydrazonodithioate, C21H19N3OS2, the amide group is twisted out of the plane through the S2C=N atoms: the C—N—N—C torsion angle is 139.71 (13)°. The pyridine ring forms dihedral angles of 52.96 (8) and 86.46 (8)° with the phenyl rings, and the latter are approximately orthogonal [dihedral angle = 76.42 (9)°]. Supramolecular chains sustained by N—H...O hydrogen bonds and propagated by glide symmetry along the c axis are found in the crystal structure. The chains are consolidated into a three-dimensional architecture by C—H...O and C—H...N interactions.

APA, Harvard, Vancouver, ISO, and other styles

7

Kansiz, Sevgi, Necmi Dege, Yildiray Topcu, Yusuf Atalay, and Snizhana V. Gaidai. "Crystal structure and Hirshfeld surface analysis of (succinato-κO)[N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine-κ5 O,N,N′,O′,O′′]nickel(II) tetrahydrate." Acta Crystallographica Section E Crystallographic Communications 74, no. 12 (November 6, 2018): 1700–1704. http://dx.doi.org/10.1107/s2056989018015359.

Full text

Abstract:

In the title compound, [Ni(C10H24N2O4)(C4H4O4)]·4H2O, the NiII cation is octahedrally coordinated by one O atom of the succinate anion and three O atoms and two N atoms from an N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine molecule. In the crystal, molecules are linked by O—H...O and C—H...O hydrogen bonds, forming a three-dimensional supramolecular architecture. Hirshfeld surface analyses and two-dimensional fingerprint plots were used to analyse the intermolecular interactions present in the crystal, indicating that the most important contributions for the crystal packing are from H...H (63.3%) and H...O/O...H (34.5%) interactions.

APA, Harvard, Vancouver, ISO, and other styles

8

Asiri, Abdullah M., Hassan M. Faidallah, Shaeel A. Al-Thabaiti, Seik Weng Ng, and Edward R. T. Tiekink. "N-Acetyl-N-[2,4-dicyano-1-(4-methoxyphenyl)-9,10-dihydrophenanthren-3-yl]acetamide." Acta Crystallographica Section E Structure Reports Online 68, no. 4 (March 24, 2012): o1177—o1178. http://dx.doi.org/10.1107/s160053681201210x.

Full text

Abstract:

In the title compound, C27H21N3O3, the cyclohexa-1,3-diene ring has a screw-boat conformation, and the fused ring system is folded, the dihedral angle between the outer benzene rings being 27.61 (6)°. TheN-acetylacetamide residue (r.m.s. deviation = 0.0935 Å) has ananticonformation and is essentially perpendicular to the benzene ring to which it is connected [dihedral angle = 89.14 (6)°]; the methoxybenzene group is also twisted out of this ring [dihedral angle = 59.47 (7)°]. The three-dimensional architecture is consolidated by C—H...O and C—H...π interactions.

APA, Harvard, Vancouver, ISO, and other styles

9

Poplaukhin, Pavel, Hadi D. Arman, and Edward R. T. Tiekink. "A one-dimensional coordination polymer, catena-poly[[[[N-ethyl-N-(pyridin-4-ylmethyl)dithiocarbamato-κ2 S,S′]zinc(II)]-μ2-N-ethyl-N-(pyridin-4-ylmethyl)dithiocarbamato-κ3 S,S′:N] 4-methylpyridine hemisolvate]." Acta Crystallographica Section E Crystallographic Communications 73, no. 8 (July 13, 2017): 1162–66. http://dx.doi.org/10.1107/s2056989017010179.

Full text

Abstract:

The title compound, {[Zn(C9H11N2S2)2]·0.5C6H7N} n , comprises two independent, but chemically similar, Zn[S2CN(Et)CH2py]2 residues and a 4-methylpyridine solvent molecule in the asymmetric unit. The Zn-containing units are connected into a one-dimensional coordination polymer (zigzag topology) propagating in the [010] direction, with one dithiocarbamate ligand bridging in a μ2-κ3 mode, employing one pyridyl N and both dithiocarbamate S atoms, while the other is κ2-chelating. In each case, the resultant ZnNS4 coordination geometry approximates a square pyramid, with the pyridyl N atom in the apical position. In the crystal, the chains are linked into a three-dimensional architecture by methyl- and pyridyl-C—H...S, methylene-C—H...N(pyridyl) and pyridyl-C—H...π(ZnS2C) interactions. The connection between the chain and the 4-methylpyridine solvent molecule is of the type pyridyl-C—H...N(4-methylpyridine).

APA, Harvard, Vancouver, ISO, and other styles

10

Macpherson, Harry, Stuart Cornes, Shen Zhou, and Kyriakos Porfyrakis. "A porphyrin-centred fullerene tetramer containing an N@C 60 substituent." Royal Society Open Science 5, no. 7 (July 2018): 180338. http://dx.doi.org/10.1098/rsos.180338.

Full text

Abstract:

An N@C 60 -containing C 60 tetramer was synthesized by quadruple 1,3-dipolar cycloaddition (Prato) reaction. This molecule demonstrates the N@C 60 qubit's ability to form covalently linked arrays. Furthermore, it provides a promising scaffold with which to measure multiple qubit–qubit interactions; which must be well characterized for a functioning quantum information processing architecture.

APA, Harvard, Vancouver, ISO, and other styles

11

Usha, M. K., S. Madan Kumar, Nitinchandra, B. Kalluraya, N. K. Lokanath, and D. Revannasiddaiah. "(E)-N′-[4-(Dimethylamino)benzylidene]-2-(4-methylphenoxy)acetohydrazide." Acta Crystallographica Section E Structure Reports Online 70, no. 2 (January 15, 2014): o140. http://dx.doi.org/10.1107/s1600536813034879.

Full text

Abstract:

In the title compound, C18H21N3O2, the dihedral angle between the benzene rings is 68.85 (11)°. In the crystal, the molecules are linked by C—H...O and N—H...O hydrogen bonds, as well as weak C—H...π contacts, forming a three-dimensional supramolecular architecture.

APA, Harvard, Vancouver, ISO, and other styles

12

Gauthier, Marion, Romain Barillot, Anne Schneider, Camille Chambon, Christian Fournier, Christophe Pradal, Corinne Robert, and Bruno Andrieu. "A functional structural model of grass development based on metabolic regulation and coordination rules." Journal of Experimental Botany 71, no. 18 (June 4, 2020): 5454–68. http://dx.doi.org/10.1093/jxb/eraa276.

Full text

Abstract:

Abstract Shoot architecture is a key component of the interactions between plants and their environment. We present a novel model of grass, which fully integrates shoot morphogenesis and the metabolism of carbon (C) and nitrogen (N) at organ scale, within a three-dimensional representation of plant architecture. Plant morphogenesis is seen as a self-regulated system driven by two main mechanisms. First, the rate of organ extension and the establishment of architectural traits are regulated by concentrations of C and N metabolites in the growth zones and the temperature. Second, the timing of extension is regulated by rules coordinating successive phytomers instead of a thermal time schedule. Local concentrations are calculated from a model of C and N metabolism at organ scale. The three-dimensional representation allows the accurate calculation of light and temperature distribution within the architecture. The model was calibrated for wheat (Triticum aestivum) and evaluated for early vegetative stages. This approach allowed the simulation of realistic patterns of leaf dimensions, extension dynamics, and organ mass and composition. The model simulated, as emergent properties, plant and agronomic traits. Metabolic activities of growing leaves were investigated in relation to whole-plant functioning and environmental conditions. The current model is an important step towards a better understanding of the plasticity of plant phenotype in different environments.

APA, Harvard, Vancouver, ISO, and other styles

13

Sreenivasa, S., S. Naveen, N. K. Lokanath, G. M. Supriya, H. N. Lakshmikantha, and P. A. Suchetan. "Crystal structures of threeN-aryl-2,2,2-tribromoacetamides." Acta Crystallographica Section E Crystallographic Communications 71, no. 9 (August 22, 2015): 1048–53. http://dx.doi.org/10.1107/s2056989015015248.

Full text

Abstract:

ThreeN-aryl-2,2,2-tribromoacetamides, namely, 2,2,2-tribromo-N-(2-fluorophenyl)acetamide, C8H5Br3FNO, (I), 2,2,2-tribromo-N-[3-(trifluoromethyl)phenyl]acetamide, C9H5Br3F3NO, (II) and 2,2,2-tribromo-N-(4-fluorophenyl)acetamide, C8H5Br3FNO, (III) were synthesized and their crystal structures were analysed. In the crystal structure of (I), C—Br...πarylinteractions connect the molecules into dimers, which in turn are connectedviaBr...Br contacts [3.6519 (12) Å], leading to the formation of a one-dimensional ladder-type architecture. The crystal structure of (II) features chains linked by N—H...O and C—H...O hydrogen bonds. Two such chains are interlinked to form ribbons through Br...Br [3.6589 (1) Å] and Br...F [3.0290 (1) Å] interactions. C—Br...πaryland C—F...πarylinteractions between the ribbons extend the supramolecular architecture of (II) from one dimension to two. In (III), the molecules are connected intoR22(8) dimersviapairs of C—H...F interactions and these dimers form ribbons through Br...Br [3.5253 (1) Å] contacts. The ribbons are further interlinked into columnsviaC—Br...O=C contacts, forming a two-dimensional architecture.

APA, Harvard, Vancouver, ISO, and other styles

14

Munzeiwa, Wisdom A., Bernard Omondi, and Vincent O. Nyamori. "Architecture and synthesis of P,N-heterocyclic phosphine ligands." Beilstein Journal of Organic Chemistry 16 (March 12, 2020): 362–83. http://dx.doi.org/10.3762/bjoc.16.35.

Full text

Abstract:

Diverse P,N-phosphine ligands reported to date have performed exceptionally well as auxiliary ligands in organometallic catalysis. Phosphines bearing 2-pyridyl moieties prominently feature in literature as compared to phosphines with five-membered N-heterocycles. This discussion seeks to paint a broad picture and consolidate different synthetic protocols and techniques for N-heterocyclic phosphine motifs. The introduction provides an account of P,N-phosphine ligands, and their structural and coordination benefits from combining heteroatoms with different basicity in one ligand. The body discusses the synthetic protocols which focus on P–C, P–N-bond formation, substrate and nucleophile types and different N-heterocycle construction strategies. Selected references are given in relation to the applications of the ligands.

APA, Harvard, Vancouver, ISO, and other styles

15

Maeda, Hiromitsu, and Hiroyuki Furuta. "N-confused porphyrins as new scaffolds for supramolecular architecture." Journal of Porphyrins and Phthalocyanines 08, no. 01 (January 2004): 67–75. http://dx.doi.org/10.1142/s1088424604000052.

Full text

Abstract:

The peripheral nitrogen of N -confused porphyrins ( NCP ) can serve as a hydrogen bonding donor and acceptor, and a metal coordination site as well. NCP forms versatile dimers with the assistance of metal ions such as Pd II, Pt II, Zn II, Cd II, Hg II, Mn II and Fe II. The square-planar divalent metal complexes of C 6 F 5-substituted NCP with Cu II, Ni II and Pd II act as efficient anion binding receptors. The doubly N -confused porphyrins ( N 2 CP ), possessing both N and NH at the periphery, form self-assembled 1-D hydrogen bonding networks, whose orientations differ in cis (zigzag) and trans (straight) isomers.

APA, Harvard, Vancouver, ISO, and other styles

16

Uflyand, Igor E., Victoria E. Burlakova, Ekaterina G. Drogan, Igor Yu Zabiyaka, Kamila A. Kydralieva, Gulsara D. Kugabaeva, and Gulzhian I. Dzhardimalieva. "Preparation of FeCo/C-N and FeNi/C-N Nanocomposites from Acrylamide Co-Crystallizates and Their Use as Lubricant Additives." Micromachines 13, no. 11 (November 16, 2022): 1984. http://dx.doi.org/10.3390/mi13111984.

Full text

Abstract:

FeCo and FeNi nanoalloy particles encapsulated in a nitrogen-doped carbonized shell (FeCo/C-N and FeNi/C-N) were synthesized by thermolysis at 400 °C of polyacrylamide complexes after frontal polymerization of co-crystallizate of Fe and Co or Ni nitrates and acrylamide. During the thermolysis of polyacrylamide complexes in a self-generated atmosphere, Co(II) or Ni(II) and Fe(III) cations are reduced to form FeCo and FeNi nanoalloy particles, while polyacrylamide simultaneously forms a nitrogen-doped carbon shell layer. This unique architecture provides high chemical and thermal stability of the resulting nanocomposites. The average crystallite size of FeCo and FeNi nanoparticles is 10 and 12 nm, respectively. The nanocomposites were studied by X-ray diffraction, atomic force microscopy, scanning electron microscopy, and high-resolution transmission electron microscopy. The nanocomposites have been tested as antifriction and antiwear additives in lubricating oils. The optimal concentrations of nanoparticles were determined, at which the antifriction and antiwear properties of the lubricant manifest themselves in the best possible way.

APA, Harvard, Vancouver, ISO, and other styles

17

Mohamad, Rapidah, Normah Awang, Nurul Farahana Kamaludin, Mukesh M. Jotani, and Edward R. T. Tiekink. "Crystal structures and Hirshfeld surface analyses of bis[N,N-bis(2-methoxyethyl)dithiocarbamato-κ2S,S′]di-n-butyltin(IV) and [N-(2-methoxyethyl)-N-methyldithiocarbamato-κ2S,S′]triphenyltin(IV)." Acta Crystallographica Section E Crystallographic Communications 74, no. 3 (February 7, 2018): 302–8. http://dx.doi.org/10.1107/s2056989018001901.

Full text

Abstract:

The crystal and molecular structures of the two title organotin dithiocarbamate compounds, [Sn(C4H9)2(C7H14NO2S2)2], (I), and [Sn(C6H5)3(C5H10NOS2)], (II), are described. Both structures feature asymmetrically bound dithiocarbamate ligands leading to a skew-trapezoidal bipyramidal geometry for the metal atom in (I) and a distorted tetrahedral geometry in (II). The complete molecule of (I) is generated by a crystallographic twofold axis (Sn site symmetry 2). In the crystal of (I), molecules self-assemble into a supramolecular array parallel to (10-1)viamethylene-C—H...O(methoxy) interactions. In the crystal of (II), supramolecular dimers are formedviapairs of weak phenyl-C—H...π(phenyl) contacts. In each of (I) and (II), the specified assemblies connect into a three-dimensional architecture without directional interactions between them. Hirshfeld surface analyses confirm the importance of H...H contacts in the molecular packing of each of (I) and (II), and in the case of (I), highlight the importance of short methoxy-H...H(butyl) contacts between layers.

APA, Harvard, Vancouver, ISO, and other styles

18

Ramalingan, Chennan, Seik Weng Ng, and Edward R. T. Tiekink. "N-(2-Fluorobenzyloxy)-1,3,5-trimethyl-2,6-diphenylpiperidin-4-imine." Acta Crystallographica Section E Structure Reports Online 68, no. 8 (July 4, 2012): o2312—o2313. http://dx.doi.org/10.1107/s1600536812029327.

Full text

Abstract:

In the title compound, C27H29FN2O, the piperidine ring has a twisted boat conformation and all ring substituents occupy equatorial positions. The dihedral angle formed between the phenyl rings is 66.71 (12)°, and the phenyl rings form dihedral angles of 46.60 (13) and 43.75 (13)° with the fluorobenzene ring, which occupies a position coplanar to the methoxy(methylidene)amine residue [N—O—C—C torsion angle = −179.5 (2)°]. In the crystal, a complex network of C—H...π interactions connects the molecules into a three-dimensional architecture.

APA, Harvard, Vancouver, ISO, and other styles

19

Qadir, Adnan M., Sevgi Kansiz, Necmi Dege, and Eiad Saif. "Crystal structure and Hirshfeld surface analysis of bis[(ethoxymethanethioyl)sulfanido](N,N,N′,N′-tetramethylethane-1,2-diamine)mercury(II)." Acta Crystallographica Section E Crystallographic Communications 77, no. 11 (October 19, 2021): 1126–29. http://dx.doi.org/10.1107/s2056989021010549.

Full text

Abstract:

The title four-coordinate mononuclear complex, [Hg(C3H5OS2)2(C6H16N2)] or [Hg(C3H5OS2)2(tmeda)] (tmeda: N,N,N′,N′-tetramethylethane-1,2-diamine), has a distorted tetrahedral geometry. The HgII ion is coordinated to two N atoms of the N,N,N′,N′-tetramethylethylenediamine ligand and two S atoms from two ethylxanthate xanthate ligands. In the crystal, molecules are linked by weak C—H...S hydrogen bonds, forming a two-dimensional supramolecular architecture in the ab plane. The most important contributions for the crystal packing are from H...H (59.3%), S...H (27.4%) and O...H (7.5%) interactions.

APA, Harvard, Vancouver, ISO, and other styles

20

Салингарос, Никос Ангелос. "ALEXANDER’S GREAT MISTAKE. WHY COULDN’T CHRISTOPHER ALEXANDER HUMANIZE ARCHITECTURE?" Академический вестник УралНИИпроект РААСН, no. 4(51) (December 30, 2021): 40–47. http://dx.doi.org/10.25628/uniip.2021.51.4.007.

Full text

Abstract:

В переведенной нами статье, представленной в августе 2021 года для международной конференции Monumentalita & Modernita-21 «Суперстили в архитектуре. Поиск новых закономерностей» (Москва, 21-22 сентября 2021), Н. Салингарос кратко излагает свою версию «болевых точек» модернистской архитектуры, не обладающей адаптивными характеристиками. Строя текст как диалог со своим учителем и другом, архитектором К. Александером, Н. Салингарос систематизирует категориальный аппарат анализа и критики модернистской архитектуры, ломающей традиционный подход, вводя такие понятия, как QWAN («качество без названия»), паттерны проектирования, визуальные паттерны, центры, дружественность архитектуры и ее элементов, мемы в архитектуре и т. д. Как и ранее, он критикует современное архитектурное образование, напрямую связывая его с дискурсом власти, и рекомендует активнее использовать коллекции паттернов проектирования, разработанные К. Александером и его коллегами. In this translated article, presented in August 2021 for the International Conference Monumentalita & Modernita-21: «Super Styles in Energy. Search for new patterns» (Moscow, September 21-22, 2021), N. Salingaros summarizes his version of the «pain points» of modernist architecture, which does not have adaptive characteristics. Building the text as a dialogue with his teacher and friend, the architect C. Alexander, N. Salingaros systematizes the categorical approach, introducing concepts such as QWAN («Quality Without A Name»), design patterns, visual patterns, centers, friendliness of architecture and its elements, memes in the architecture, etc. As before, he criticizes modern architectural education, directly linking it with the discourse of power, recommends more active use of the collections of design patterns developed by C. Alexander and his colleagues.

APA, Harvard, Vancouver, ISO, and other styles

21

Sreenivasa, S., B. S. Palakshamurthy, E. Suresha, J. Tonannavar, Yenagi Jayashree, and P. A. Suchetan. "N-[(2-Chlorophenyl)sulfonyl]-2-methoxybenzamide." Acta Crystallographica Section E Structure Reports Online 69, no. 11 (October 31, 2013): o1716. http://dx.doi.org/10.1107/s1600536813029012.

Full text

Abstract:

The title compound, C14H12ClNO4S, crystallizes with two molecules in the asymmetric unit. The dihedral angles between the benzene rings are 89.68 (1) (molecule 1) and 82.9 (1)° (molecule 2). In each molecule, intramolecular N—H...O hydrogen bonds between the amide H atom and the methoxy O atom generateS(6) loops. In the crystal, molecule 2 is linked into inversion dimers through pairs of C—H...O interactions, forming anR22(8) ring motif. Molecules 1 and 2 are further linked along theb-axis direction through C—H...π interactions. The crystal structure is further stabilized by several π–π stacking interactions [centroid–centroid separations = 3.7793 (1), 3.6697 (1) and 3.6958 (1) Å], thus generating a three-dimensional architecture.

APA, Harvard, Vancouver, ISO, and other styles

22

Zhang, Huaiyue, Hongtao Cui, Jing Li, Yuanyuan Liu, Yanzhao Yang, and Meiri Wang. "Frogspawn inspired hollow Fe3C@N–C as an efficient sulfur host for high-rate lithium–sulfur batteries." Nanoscale 11, no. 44 (2019): 21532–41. http://dx.doi.org/10.1039/c9nr07388d.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Wang, Shuhai, Jun Teng, Yanyu Xie, Zhang-Wen Wei, Yanan Fan, Ji-Jun Jiang, Hai-Ping Wang, Heguang Liu, Dawei Wang, and Cheng-Yong Su. "Embedding CoO nanoparticles in a yolk–shell N-doped porous carbon support for ultrahigh and stable lithium storage." Journal of Materials Chemistry A 7, no. 8 (2019): 4036–46. http://dx.doi.org/10.1039/c8ta11007g.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Yeo, Chien, and Edward Tiekink. "N-(4-Bromophenyl)methoxycarbothioamide." Molbank 2018, no. 3 (August 17, 2018): M1012. http://dx.doi.org/10.3390/m1012.

Full text

Abstract:

The synthesis, spectroscopic and crystallographic characterisation of the title compound, O-methyl-N-4-bromophenyl thiocarbamate, MeOC(=S)N(H)PhBr-4 (1), are described. Spectroscopy confirmed the formation of the compound and the molecular structure was determined crystallographically. Two independent but chemically similar molecules comprise the asymmetric unit of 1. The C‒S and C‒N bond lengths confirm the presence of the thioamide tautomer. The thione-S and amide-N‒H atoms are syn, enabling the formation of amide-N‒H…S(thione) hydrogen bonds between the two independent molecules that generates a two-molecule aggregate via an eight-membered {…HNCS}2 synthon. The aggregates are connected into a three-dimensional architecture via weak intermolecular interactions, including Br…π(4-bromophenyl), S…π(4-bromophenyl), and weak Br…S halogen bonding contacts. The overall molecular conformation, thioamide tautomer, and the presence of amide-N‒H…S(thione) hydrogen bonding in the crystal conform with expectation for this class of compound.

APA, Harvard, Vancouver, ISO, and other styles

25

Kajornprai, Todsapol, Putita Katesripongsa, Sang Yong Nam, Zuratul Ain Abdul Hamid, Yupaporn Ruksakulpiwat, Nitinat Suppakarn, and Tatiya Trongsatitkul. "Potential Applications of Thermoresponsive Poly(N-Isoproplacrylamide)-Grafted Nylon Membranes: Effect of Grafting Yield and Architecture on Gating Performance." Polymers 15, no. 3 (January 18, 2023): 497. http://dx.doi.org/10.3390/polym15030497.

Full text

Abstract:

This study illustrated the potential applications of thermoresponsive poly(N-isopropylacrylamide) (PNIPAm) grafted nylon membranes with different grafting yields and grafting architecture. The thermoresponsive gating performance at temperatures below and above the lower critical solution temperature (LCST) of PNIPAm (32 °C) were demonstrated. The linear PNIPAm-grafted nylon membrane exhibited a sharp response over the temperature range 20–40 °C. The grafting yield of 25.5% and 21.9%, for linear and crosslinked PNIPAm respectively, exhibited highest thermoresponsive gating function for water flux and had a stable and repeatable “open-closed” switching function over 5 cycle operations. An excellent oil/water separation was obtained at T < 32 °C, at which the hydrophilic behavior was observed. The linear PNIPAm-grafted nylon membrane with 35% grafting yield had the highest separation efficiency of 99.7%, while PNIPAm structures were found to be independent of the separation efficiency. In addition, the membranes with thermoresponsive gas permeability were successfully achieved. The O2 and CO2 transmission rates through the PNIPAm-grafted nylon membranes decreased when the grafting yield increased, showing the better gas barrier property. The permeability ratio of CO2 to O2 transmission rates of both PNIPAm architectures at 25 °C and 35 °C were around 0.85 for low grafting yields, and approximately 1 for high grafting yields. Ultimately, this study demonstrated the possibility of using these thermoresponsive smart membranes in various applications.

APA, Harvard, Vancouver, ISO, and other styles

26

Novotná, Radka, and Zdeněk Trávníček. "Infinite ladder-like chains organized into a three-dimensional zigzag supramolecular architecture in 9-deazahypoxanthine." Acta Crystallographica Section C Crystal Structure Communications 69, no. 2 (January 5, 2013): 158–61. http://dx.doi.org/10.1107/s0108270112050767.

Full text

Abstract:

The asymmetric unit of the title compound, C6H5N3O, consists of discrete molecules of 9-deazahypoxanthine [systematic name: 3H-pyrrolo[3,2-d]pyrimidin-4(5H)-one]. The structure displays N—H...O hydrogen bonding, connecting the molecules into centrosymmetric dimers. These dimers are then connected by N—H...N hydrogen bonds into a ladder-like chain along thecaxis. The secondary structure is stabilized by weak noncovalent contacts of the C—H...O and C—H...C types, as well as by π–π stacking interactions, which organize the structure into a zigzag architecture.

APA, Harvard, Vancouver, ISO, and other styles

27

Oloyede, Hammed Olawale, Joseph Anthony Orighomisan Woods, Helmar Görls, Winfried Plass, and Abiodun Omokehinde Eseola. "N-donor-stabilized Pd(II) species supported by sulphonamide-azo ligands: Ligand architecture, solvent co-ligands, C–C coupling." Journal of Molecular Structure 1199 (January 2020): 127030. http://dx.doi.org/10.1016/j.molstruc.2019.127030.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Alelwani, Raed, Muhammad Waseem Ahmad, and Yacine Rezgui. "Public Perception of Vernacular Architecture in the Arabian Peninsula: The Case of Rawshan." Buildings 10, no. 9 (August 31, 2020): 151. http://dx.doi.org/10.3390/buildings10090151.

Full text

Abstract:

This research extends Hasan Fathy’s (1986) principle of vernacular architecture by focusing on the Rawshan through an investigation of two criteria: aesthetics and energy efficiency. The paper discusses the views of both the Saudi public and key decision-makers on reviving vernacular architecture in the context of Saudi Arabia’s rapidly developing economy, characterized by relatively high rates of energy consumption and CO2 emissions. This research explores (a) the interaction in domestic buildings of Saudi occupants with their windows, and how these are perceived as an interface with the external environment; (b) awareness and knowledge of the use of shading elements (such as Rawshans) to reduce the use of artificial lighting while maintaining indoor privacy; (c) Saudi awareness of, and familiarity with, the Rawshan as a vernacular element and a secular architectural tradition; and (d) Saudi views on the revival of traditional architectural elements with a focus on the Rawshan. An online survey (n = 812) was conducted across Saudi Arabia complemented by interviews with expert decision-makers (n = 23) to (a) assess criteria such as privacy, aesthetics, daylight, ventilation, and energy consumption in Saudi residences and (b) investigate the level of acceptance of an optimized retrofitted Rawshan design.

APA, Harvard, Vancouver, ISO, and other styles

29

Liu, Fuhong, Yan Ding, Qiuyu Li, and Liping Zhang. "A two-dimensional Zn coordination polymer with a three-dimensional supramolecular architecture." Acta Crystallographica Section E Crystallographic Communications 73, no. 10 (September 5, 2017): 1402–4. http://dx.doi.org/10.1107/s2056989017012452.

Full text

Abstract:

The title compound, poly[bis{μ2-4,4′-bis[(1,2,4-triazol-1-yl)methyl]biphenyl-κ2N4:N4′}bis(nitrato-κO)zinc(II)], [Zn(NO3)2(C18H16N6)2]n, is a two-dimensional zinc coordination polymer constructed from 4,4′-bis[(1H-1,2,4-triazol-1-yl)methyl]-1,1′-biphenyl units. It was synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. The ZnIIcation is located on an inversion centre and is coordinated by two O atoms from two symmetry-related nitrate groups and four N atoms from four symmetry-related 4,4′-bis[(1H-1,2,4-triazol-1-yl)methyl]-1,1′-biphenyl ligands, forming a distorted octahedral {ZnN4O2} coordination geometry. The linear 4,4′-bis[(1H-1,2,4-triazol-1-yl)methyl]-1,1′-biphenyl ligand links two ZnIIcations, generating two-dimensional layers parallel to the crystallographic (132) plane. The parallel layers are connected by C—H...O, C—H...N, C—H...π and π–π stacking interactions, resulting in a three-dimensional supramolecular architecture.

APA, Harvard, Vancouver, ISO, and other styles

30

Sichevych, Olga, Yurii Prots, Walter Schnelle, Frank R. Wagner, and Yuri Grin. "Polycation–Polyanion Architecture of the Intermetallic Compound Mg3−xGa1+xIr." Molecules 27, no. 3 (January 20, 2022): 659. http://dx.doi.org/10.3390/molecules27030659.

Full text

Abstract:

Mg3−xGa1+xIr (x = 0.05) was synthesized by direct reaction of the elements in welded tantalum containers at 1200 °C and subsequent annealing at 500 °C for 30 days. Its crystal structure represents a new prototype and was determined by single-crystal technique as follows: space group P63/mcm, Pearson symbol hP90, Z = 18, a = 14.4970(3) Å, c = 8.8638(3) Å. The composition and atomic arrangement in Mg3GaIr do not follow the 8–N rule due to the lack of valence electrons. Based on chemical bonding analysis in positional space, it was shown that the title compound has a polycationic–polyanionic organization. In comparison with other known intermetallic substances with this kind of bonding pattern, both the polyanion and the polyanion are remarkably complex. Mg3−xGa1+xIr is an example of how the general organization of intermetallic substances (e.g., formation of polyanions and polycations) can be understood by extending the principles of 8–N compounds to electron-deficient materials with multi-atomic bonding.

APA, Harvard, Vancouver, ISO, and other styles

31

Jotani, Mukesh M., Hadi D. Arman, Pavel Poplaukhin, and Edward R. T. Tiekink. "Bis(N,N-diethyldithiocarbamato-κ2S,S′)(3-hydroxypyridine-κN)zinc and bis[N-(2-hydroxyethyl)-N-methyldithiocarbamato-κ2S,S′](3-hydroxypyridine-κN)zinc: crystal structures and Hirshfeld surface analysis." Acta Crystallographica Section E Crystallographic Communications 72, no. 12 (November 1, 2016): 1700–1709. http://dx.doi.org/10.1107/s205698901601728x.

Full text

Abstract:

The common feature of the molecular structures of the title compounds, [Zn(C5H10NS2)2(C5H5NO)], (I), and [Zn(C4H8NOS2)2(C5H5NO)], (II), are NS4donor sets derived fromN-bound hydroxypyridyl ligands and asymmetrically chelating dithiocarbamate ligands. The resulting coordination geometries are highly distorted, being intermediate between square pyramidal and trigonal bipyramidal for both independent molecules comprising the asymmetric unit of (I), and significantly closer towards square pyramidal in (II). The key feature of the molecular packing in (I) is the formation of centrosymmetric, dimeric aggregates sustained by pairs of hydroxy-O—H...S(dithiocarbamate) hydrogen bonds. The aggregates are connected into a three-dimensional architecture by methylene-C—H...O(hydroxy) and methyl-C—H...π(chelate) interactions. With greater hydrogen-bonding potential, supramolecular chains along thecaxis are formed in the crystal of (II), sustained by hydroxy-O—H...O(hydroxy) hydrogen bonds, with ethylhydroxy and pyridylhydroxy groups as the donors, along with ethylhydroxy-O—H...S(dithiocarbamate) hydrogen bonds. Chains are connected into layers in theacplane by methylene-C—H...π(chelate) interactions and these stack along thebaxis, with no directional interactions between them. An analysis of the Hirshfeld surfaces clearly distinguished the independent molecules of (I) and reveals the importance of the C—H...π(chelate) interactions in the packing of both (I) and (II).

APA, Harvard, Vancouver, ISO, and other styles

32

Georgescu, Roxana, Zuanning Yuan, Lin Bai, Ruda de Luna Almeida Santos, Jingchuan Sun, Dan Zhang, Olga Yurieva, Huilin Li, and Michael E. O’Donnell. "Structure of eukaryotic CMG helicase at a replication fork and implications to replisome architecture and origin initiation." Proceedings of the National Academy of Sciences 114, no. 5 (January 17, 2017): E697—E706. http://dx.doi.org/10.1073/pnas.1620500114.

Full text

Abstract:

The eukaryotic CMG (Cdc45, Mcm2–7, GINS) helicase consists of the Mcm2–7 hexameric ring along with five accessory factors. The Mcm2–7 heterohexamer, like other hexameric helicases, is shaped like a ring with two tiers, an N-tier ring composed of the N-terminal domains, and a C-tier of C-terminal domains; the C-tier contains the motor. In principle, either tier could translocate ahead of the other during movement on DNA. We have used cryo-EM single-particle 3D reconstruction to solve the structure of CMG in complex with a DNA fork. The duplex stem penetrates into the central channel of the N-tier and the unwound leading single-strand DNA traverses the channel through the N-tier into the C-tier motor, 5′-3′ through CMG. Therefore, the N-tier ring is pushed ahead by the C-tier ring during CMG translocation, opposite the currently accepted polarity. The polarity of the N-tier ahead of the C-tier places the leading Pol ε below CMG and Pol α-primase at the top of CMG at the replication fork. Surprisingly, the new N-tier to C-tier polarity of translocation reveals an unforeseen quality-control mechanism at the origin. Thus, upon assembly of head-to-head CMGs that encircle double-stranded DNA at the origin, the two CMGs must pass one another to leave the origin and both must remodel onto opposite strands of single-stranded DNA to do so. We propose that head-to-head motors may generate energy that underlies initial melting at the origin.

APA, Harvard, Vancouver, ISO, and other styles

33

Jordan, Marie-Odile, Gilles Vercambre, Jacques Le Bot, Stéphane Adamowicz, Laurent Gomez, and Loïc Pagès. "Autumnal nitrogen nutrition affects the C and N storage and architecture of young peach trees." Trees 25, no. 2 (October 30, 2010): 333–44. http://dx.doi.org/10.1007/s00468-010-0509-7.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Shen, Jie, Gu-Ping Tang, and Xiu-Rong Hu. "Crystal structure of (S)-5-chloro-N-({2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]oxazolidin-5-yl}methyl)thiophene-2-carboxamide." Acta Crystallographica Section E Crystallographic Communications 74, no. 1 (January 1, 2018): 51–54. http://dx.doi.org/10.1107/s2056989017017819.

Full text

Abstract:

The asymmetric unit of the crystal of the title compound (common name rivaroxaban), C19H18ClN3O5, contains two rivaroxaban molecules with different conformations; the C—C—N—C torsion angles between the oxazolidine and thiophene rings are −171.1 (7) and −106.8 (9)° in the two independent molecules. In the crystal, classical N—H...O hydrogen bonds and weak C—H...O hydrogen bonds link the molecules into a three-dimensional supramolecular architecture.

APA, Harvard, Vancouver, ISO, and other styles

35

Chainok, Kittipong, Sureerat Makmuang, and Filip Kielar. "Crystal structures of (E)-N′-(2-hydroxy-5-methylbenzylidene)isonicotinohydrazide and (E)-N′-(5-fluoro-2-hydroxybenzylidene)isonicotinohydrazide." Acta Crystallographica Section E Crystallographic Communications 72, no. 7 (June 17, 2016): 980–83. http://dx.doi.org/10.1107/s2056989016009762.

Full text

Abstract:

Two derivatives of the well-known iron chelator, (E)-N′-(2-hydroxybenzylidene)isonicotinohydrazide (SIH), substituted in the 5-position of the 2-hydroxybenzene ring by a methyl and a fluorine groupviz.(E)-N′-(2-hydroxy-5-methylbenzylidene)isonicotinohydrazide, C14H13N3O2, (I), and (E)-N′-(5-fluoro-2-hydroxybenzylidene)isonicotinohydrazide, C13H10FN3O2, (II), have been prepared and characterized by single-crystal X-ray diffraction,1H NMR and mass spectrometry. The molecules of both compounds deviate slightly from planarity [r.m.s. deviations are 0.145 and 0.110 Å for (I) and (II), respectively] and adopt anEconformation with respect to the double bond of the hydrazone bridge. In each molecule, there is an intramolecular O—H...N hydrogen bond forming anS(6) ring motif. The dihedral angles between the mean planes of the isonicotinoyl ring and the cresol ring in (I) or the fluorophenol ring in (II) are 10.49 (6) and 9.43 (6)°, respectively. In the crystals of both compounds, zigzag chains are formedviaN—H...N hydrogen bonds, in the [10-1] direction for (I) and [010] for (II). In (I), the chains are linked by weak C—H...π and π–π stacking interactions [centroid-to-centroid distances = 3.6783 (8) Å; inter-planar angle = 10.94 (5)°], leading to the formation of a three-dimensional supramolecular architecture. In (II), adjacent chains are connected through C—H...O hydrogen bonds to form sheets parallel to (100), which encloseR44(30) ring motifs. The sheets are linked by weak C—H...π and π–π [centroid-to-centroid distance = 3.7147 (8) Å; inter-planar angle = 10.94 (5)°] interactions, forming a three-dimensional supramolecular architecture.

APA, Harvard, Vancouver, ISO, and other styles

36

Chavda, Jitesh T., and G. R. Dodagoudar. "Finite Element Evaluation of Vertical Bearing Capacity Factors $$N_{c}^{\prime }$$ N c ′ , $$N_{q}^{\prime }$$ N q ′ and $$N_{\gamma }^{\prime }$$ N γ ′ for Ring Footings." Geotechnical and Geological Engineering 37, no. 2 (July 25, 2018): 741–54. http://dx.doi.org/10.1007/s10706-018-0645-1.

Full text

APA, Harvard, Vancouver, ISO, and other styles

37

Brandwajn, Alexandre, and Thomas Begin. "Reduced complexity in M/Ph/c/N queues." Performance Evaluation 78 (August 2014): 42–54. http://dx.doi.org/10.1016/j.peva.2014.06.001.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Tiekink, Edward R. T., Solange M. S. V. Wardell, James L. Wardell, Marcelle de Lima Ferreira, Marcus V. N. de Souza, and Carlos R. Kaiser. "4-[(E)-2-(2-Chlorobenzylidene)hydrazin-1-yl]quinolin-1-ium chloride dihydrate." Acta Crystallographica Section E Structure Reports Online 68, no. 6 (May 23, 2012): o1850—o1851. http://dx.doi.org/10.1107/s1600536812022660.

Full text

Abstract:

In the title hydrated salt, C16H13ClN3 +·Cl−·2H2O, a small twist is evident in the cation so that the chlorobenzene ring is not coplanar with the central hydrazinyl group [the N—C—C—C torsion angle = −4.8 (12)°]. The conformation about the imine N=C bond [1.284 (10) Å] is E. The components of the structure are connected into a three-dimensional architecture via O—H...O, O—H...Cl and N—H...Cl hydrogen bonds. One water H atom is disposed over two sites of equal occupancy.

APA, Harvard, Vancouver, ISO, and other styles

39

Porfyrakis, Kyriakos. "(Invited) N@C₆₀ and N@C₇₀ for Quantum Information Processing: Beyond Qubits." ECS Meeting Abstracts MA2022-01, no. 11 (July 7, 2022): 817. http://dx.doi.org/10.1149/ma2022-0111817mtgabs.

Full text

Abstract:

Endohedral fullerenes such as N@C60, where a single atomic nitrogen is trapped inside the fullerene cage, have been proposed as qubit architectures due to the remarkably long relaxation times of their p-electron spins (T1 = 0.375 ms, T2 = 0.25 ms). Molecular quantum computers are still at the fringes of the field as recent developments have focused on other implementations such as superconducting qubits. However, molecular approaches present some advantages such as the ability to use chemical functionalization for scaling up qubit architectures. This, combined with continuous progress on miniaturization of electrodes via e-beam lithography and other techniques, means that molecular approaches will continue to be of interest. In this talk, I will review the field of fullerene-based quantum information processing. I will present progress on the synthesis, chemical functionalization and alignment of N@C60 and N@C70 in different matrices. Recently, we were able to align N@C60 and N@C70 derivatives in a liquid crystal matrix with ordering parameter Ozz = 0.61. With the aligned samples, we were able to achieve addressability of the available 4-electron spin levels in endohedral nitrogen by coherent manipulations. Furthermore, these functionalized molecules give rise to endohedral fullerene qudits: multi-level computational units alternative to the conventional 2-level qubits. Qudits offer a larger state space for encoding information and thus can offer enhancement of quantum algorithm efficiency. Indeed, we were able to demonstrate the first ever geometric phase using pulsed EPR; something that was first proposed over 30 years ago!

APA, Harvard, Vancouver, ISO, and other styles

40

Yang, Jing, Shiqi Xing, Jianbin Zhou, Yun Cheng, Lei Shi, and Qing Yang. "The controlled construction of a ternary hybrid of monodisperse Ni3S4 nanorods/graphitic C3N4 nanosheets/nitrogen-doped graphene in van der Waals heterojunctions as a highly efficient electrocatalyst for overall water splitting and a promising anode material for sodium-ion batteries." Journal of Materials Chemistry A 7, no. 8 (2019): 3714–28. http://dx.doi.org/10.1039/c8ta07253a.

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Sapper, André, Guilherme Paim, Eduardo Antônio César Da Costa, and Sergio Bampi. "Exploring the CORDIC Algorithm and Clock-Gating for Power-Efficient Fast Fourier Transform Hardware Architectures." Journal of Integrated Circuits and Systems 16, no. 2 (August 15, 2021): 1–11. http://dx.doi.org/10.29292/jics.v16i2.226.

Full text

Abstract:

This work explores hardware-oriented optimizations for the CORDIC (COordinate Rotation Digital Computer) algorithm investigating the power-efficiency improvements employing N-point Fast Fourier Transform (FFT) hardware architectures. We introduced three hardware-oriented optimizations for the CORDIC: (a) improving the signal extension, (b) removing the angle accumulation and (c) eliminating the redundancies in the iterations, both unnecessary when processing the FFT processing. Fully sequential FFT architectures of 32, 64, 128, and 256 points were synthesized employing ST 65 nm standard cell libraries. The results show up to 38% of power savings on average when using our best CORDIC optimization proposal to the FFT architecture comparing to the explicit multiply-based butterfly version. Moreover, when combining our best CORDIC optimization with the clock-gating technique, the power savings rises to 78.5% on average for N-point FFT.

APA, Harvard, Vancouver, ISO, and other styles

42

Shakuntala, K., S. Naveen, N. K. Lokanath, P. A. Suchetan, and M. Abdoh. "Different supramolecular architectures mediated by different weak interactions in the crystals of three N-aryl-2,5-dimethoxybenzenesulfonamides." Acta Crystallographica Section C Structural Chemistry 73, no. 10 (September 29, 2017): 833–44. http://dx.doi.org/10.1107/s2053229617013195.

Full text

Abstract:

The synthesis and evaluation of the pharmacological activities of molecules containing the sulfonamide moiety have attracted interest as these compounds are important pharmacophores. The crystal structures of three closely related N-aryl-2,5-dimethoxybenzenesulfonamides, namely N-(2,3-dichlorophenyl)-2,5-dimethoxybenzenesulfonamide, C14H13Cl2NO4S, (I), N-(2,4-dichlorophenyl)-2,5-dimethoxybenzenesulfonamide, C14H13Cl2NO4S, (II), and N-(2,4-dimethylphenyl)-2,5-dimethoxybenzenesulfonamide, C16H19NO4S, (III), are described. The asymmetric unit of (I) consists of two symmetry-independent molecules, while those of (II) and (III) contain one molecule each. The molecular conformations are stabilized by different intramolecular interactions, viz. C—H...O interactions in (I), N—H...Cl and C—H...O interactions in (II), and C—H...O interactions in (III). The crystals of the three compounds display different supramolecular architectures built by various weak intermolecular interactions of the types C—H...O, C—H...Cl, C—H...π(aryl), π(aryl)–π(aryl) and Cl...Cl. A detailed Hirshfeld surface analysis of these compounds has also been conducted in order to understand the relationship between the crystal structures. The d norm and shape-index surfaces of (I)–(III) support the presence of various intermolecular interactions in the three structures. Analysis of the fingerprint plots reveals that the greatest contribution to the Hirshfeld surfaces is from H...H contacts, followed by H...O/O...H contacts. In addition, comparisons are made with the structures of some related compounds. Putative N—H...O hydrogen bonds are observed in 29 of the 30 reported structures, wherein the N—H...O hydrogen bonds form either C(4) chain motifs or R 2 2(8) rings. Further comparison reveals that the characteristics of the N—H...O hydrogen-bond motifs, the presence of other interactions and the resultant supramolecular architecture is largely decided by the position of the substituents on the benzenesulfonyl ring, with the nature and position of the substituents on the aniline ring exerting little effect. On the other hand, the crystal structures of (I)–(III) display several weak interactions other than the common N—H...O hydrogen bonds, resulting in supramolecular architectures varying from one- to three-dimensional depending on the nature and position of the substituents on the aniline ring.

APA, Harvard, Vancouver, ISO, and other styles

43

Lal Zakaria, Negin, Mehrdad Pourayoubi, Mahsa Eghbali Toularoud, Michal Dušek, and Eliska Skorepova. "Structural differences/similarities of diastereotopic groups in three new chiral phosphoramides." Acta Crystallographica Section C Structural Chemistry 77, no. 4 (March 29, 2021): 186–96. http://dx.doi.org/10.1107/s2053229621002047.

Full text

Abstract:

The crystal structures of two single-enantiomer amidophosphoesters with an (O)2P(O)(N) skeleton and one single-enantiomer phosphoric triamide with an (N)2P(O)(N) skeleton were studied. The compounds are diphenyl [(R)-(+)-α-4-dimethylbenzylamido]phosphate, (I), and diphenyl [(S)-(−)-α-4-dimethylbenzylamido]phosphate, (II), both C21H22NO3P, and N-(2,6-difluorobenzoyl)-N′,N′′-bis[(R)-(+)-α-ethylbenzyl]phosphoric triamide, C25H28F2N3O2P, (III). The asymmetric units contain two amidophosphoester molecules for (I) and (II), and one phosphoric triamide molecule for (III). In the crystal structures of (I) and (II), molecules are assembled in a similar one-dimensional chiral ribbon architecture, but with almost a mirror-image relationship with respect to each other through N—H...O(P) and C—H...O(P) hydrogen bonds along [010]. In the crystal structure of (III), the chiral tape architecture along [100] is mediated by N—H...O(P) and N—H...O(C) hydrogen bonds, and the tapes are connected into slabs by C—H...O interactions (along the ab plane). The differences/similarities of the two diastereotopic phenoxy groups in (I)/(II) and the two chiral amine fragments in (III) were studied on the grounds of geometry, conformation and contribution to the crystal packing, as well as 1H and 13C signals in a solution NMR study.

APA, Harvard, Vancouver, ISO, and other styles

44

Berger, Bonnie, and John Rompel. "Simulating (log c n )-wise independence in NC." Journal of the ACM (JACM) 38, no. 4 (October 1991): 1026–46. http://dx.doi.org/10.1145/115234.115347.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Brietzke, Thomas, Daniel Kässler, Alexandra Kelling, Uwe Schilde, and Hans-Jürgen Holdt. "(1,6,7,12-Tetraazaperylene-κ2N,N′)bis(4,4′,5,5′-tetramethyl-2,2′-bipyridyl-κ2N,N′)ruthenium(II) bis(hexafluoridophosphate) acetonitrile trisolvate." Acta Crystallographica Section E Structure Reports Online 70, no. 6 (May 31, 2014): m238—m239. http://dx.doi.org/10.1107/s1600536814011969.

Full text

Abstract:

In the title compound,rac-[Ru(C14H16N2)2(C16H8N4)](PF6)2·3C2H3N, discrete dimers of complex cations, [Ru(tmbpy)2tape]2+, of opposite chirality are formed (tmbpy = tetramethylbipyridine; tape = tetraazaperylene), held together by π–π stacking interactions between the tetraazaperylene moieties with centroid–centroid distances in the range 3.563 (3)–3.837 (3) Å. These interactions exhibit a parallel displaced π–π stacking mode. Additional weak C—H...π-ring and C—H...N and C—H...F interactions are found, leading to a three-dimensional architecture. The RuIIatom is coordinated in a distorted octahedral geometry. The counter-charge is provided by two hexafluoridophosphate anions and the asymmetric unit is completed by three acetonitrile solvent molecules of crystallization. Four F atoms of one PF6−anion are disordered over three sets of sites with occupancies of 0.517 (3):0.244 (3):0.239 (3). Two acetonitrile solvent molecules are highly disordered and their estimated scattering contribution was subtracted from the observed diffraction data using the SQUEEZE option inPLATON[Spek (2009).Acta Cryst.D65, 148–155].

APA, Harvard, Vancouver, ISO, and other styles

46

He, Jiarui, Weiqiang Lv, Yuanfu Chen, Jie Xiong, Kechun Wen, Chen Xu, Wanli Zhang, Yanrong Li, Wu Qin, and Weidong He. "Direct impregnation of SeS2 into a MOF-derived 3D nanoporous Co–N–C architecture towards superior rechargeable lithium batteries." Journal of Materials Chemistry A 6, no. 22 (2018): 10466–73. http://dx.doi.org/10.1039/c8ta02434k.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Tan, Sang Loon, and Edward R. T. Tiekink. "2,2′-(Disulfanediyl)dibenzoic acid N,N-dimethylformamide monosolvate: crystal structure, Hirshfeld surface analysis and computational study." Acta Crystallographica Section E Crystallographic Communications 76, no. 7 (June 26, 2020): 1150–57. http://dx.doi.org/10.1107/s2056989020008257.

Full text

Abstract:

The title 1:1 solvate, C14H10O4S2·C3H7NO, features a twisted molecule of 2,2′-dithiodibenzoic acid (DTBA), with the central C—S—S—C torsion angle being −88.57 (6)°, and a molecule of dimethylformamide (DMF). The carboxylic acid groups are, respectively, close to co-planar and twisted with respect to the benzene rings to which they are connected as seen in the CO2/C6 torsion angles of 1.03 (19) and 7.4 (2)°. Intramolecular, hypervalent S←O interactions are noted [S...O = 2.6140 (9) and 2.6827 (9) Å]. In the crystal, four-molecule aggregates are formed via DTBA-O—H...O(DMF) and DTBA-O—H...O(DTBA) hydrogen bonding, the latter via an eight-membered {...OHCO}2 homosynthon. These are linked into supramolecular layers parallel to (011) via benzene-C—H...O(DTBA) and DTBA-C=O...π(benzene) interactions, with the connections between these, giving rise to a three-dimensional architecture, being of the type benzene-C—H...π(benzene). An analysis of the calculated Hirshfeld surfaces indicates, in addition to the aforementioned intermolecular contacts, the presence of stabilizing interactions between a benzene ring and a quasi-π-system defined by O—H...O hydrogen bonds between a DTBA dimer, i.e. the eight-membered {...OCOH}2 ring system, and between a benzene ring and a quasi-π(OCOH...OCH) system arising from the DTBA-O—H...O(DMF) hydrogen bond. The inter-centroid separations are 3.65 and 3.49 Å, respectively.

APA, Harvard, Vancouver, ISO, and other styles

48

Swinton Darious, Robert, Packianathan Thomas Muthiah, and Franc Perdih. "Supramolecular architecture in a co-crystal of the N(7)—H tautomeric form ofN6-benzoyladenine with adipic acid (1/0.5)." Acta Crystallographica Section E Crystallographic Communications 72, no. 6 (May 13, 2016): 805–8. http://dx.doi.org/10.1107/s2056989016007581.

Full text

Abstract:

The asymmetric unit of the title co-crystal, C12H9N5O·0.5C6H10O4, consists of one molecule ofN6-benzoyladenine (BA) and one half-molecule of adipic acid (AA), the other half being generated by inversion symmetry. The dihedral angle between the adenine and phenyl ring planes is 26.71 (7)°. TheN6-benzoyladenine molecule crystallizes in the N(7)—H tautomeric form with three non-protonated N atoms. This tautomeric form is stabilized by intramolecular N—H...O hydrogen bonding between the carbonyl (C=O) group and the N(7)—H hydrogen atom on the Hoogsteen face of the purine ring, forming anS(7) ring motif. The two carboxyl groups of adipic acid interact with the Watson–Crick face of the BA molecules through O—H...N and N—H...O hydrogen bonds, generating anR22(8) ring motif. The latter units are linked by N—H...N hydrogen bonds, forming layers parallel to (10-5). A weak C—H...O hydrogen bond is also present, linking adipic acid molecules in neighbouring layers, enclosingR22(10) ring motifs and forming a three-dimensional structure. C=O...π and C—H...π interactions are also present in the structure.

APA, Harvard, Vancouver, ISO, and other styles

49

Cai, Hua, Ying Guo, and Jian-Gang Li. "A one-dimensional coordination polymer createdvia in situligand synthesis involving C—N bond formation." Acta Crystallographica Section C Crystal Structure Communications 69, no. 11 (October 5, 2013): 1307–10. http://dx.doi.org/10.1107/s010827011302475x.

Full text

Abstract:

The novel cadmium complexcatena-poly[cadmium(II)-μ3-{2-[3-(pyridin-2-yl)-1H-pyrazol-1-yl]butanedioato}], [Cd(C12H9N3O4)]n, has been prepared by the conjugate addition reaction of 2-(1H-pyrazol-3-yl)pyridine to fumaric acid in the presence of Cd(OAc)2·3H2O (OAc is acetate) at 413 K. Single-crystal X-ray diffraction analysis reveals that the complex consists of one-dimensional ladders constructed from [Cd2(COO)2] dimeric subunits. A combination of hydrogen bonding and π–π stacking interactions extend the one-dimensional ladders into a three-dimensional supramolecular architecture.

APA, Harvard, Vancouver, ISO, and other styles

50

Zukerman-Schpector, Julio, Cássio da S. Dias, Ricardo S. Schwab, Mukesh M. Jotani, and Edward R. T. Tiekink. "4-(4-Acetyl-5-methyl-1H-1,2,3-triazol-1-yl)benzonitrile: crystal structure and Hirshfeld surface analysis." Acta Crystallographica Section E Crystallographic Communications 74, no. 9 (August 10, 2018): 1195–200. http://dx.doi.org/10.1107/s2056989018010885.

Full text

Abstract:

The title compound, C12H10N4O, comprises a central 1,2,3-triazole ring (r.m.s. deviation = 0.0030 Å) flanked by N-bound 4-cyanophenyl and C-bound acetyl groups, which make dihedral angles of 54.64 (5) and 6.8 (3)° with the five-membered ring, indicating a twisted molecule. In the crystal, the three-dimensional architecture is sustained by carbonyl-C=O...π(triazoyl), cyano-C[triple-bond]N...π(triazoyl) (these interactions are shown to be attractive based on non-covalent interaction plots) and π–π stacking interactions [intercentroid separation = 3.9242 (9) Å]. An analysis of the Hirshfeld surface shows the important contributions made by H...H (35.9%) and N...H (26.2%) contacts to the overall surface, as well as notable contributions by O...H (9.9%), C...H (8.7%), C...C (7.3%) and C...N (7.2%) contacts.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Architecture, n.e.c'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles