Artykuły w czasopismach: „Magnetic Organic Molecules”

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Awaga, Kunio, Eugenio Coronado i Marc Drillon. "Hybrid Organic/Inorganic Magnets". MRS Bulletin 25, nr 11 (listopad 2000): 52–57. http://dx.doi.org/10.1557/mrs2000.224.

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The construction of more and more complex systems starting from elemental molecular units used as building blocks is propelling several disciplines of burgeoning interest, such as supramolecular chemistry, molecular electronics, and molecular magnetism. In the particular context of magnetic molecular materials, an attractive possibility for adding complexity to the material is to use a hybrid approach in which an organic component is combined with an inorganic one. Both purely organic and purely inorganic approaches (see the articles in this issue by Veciana and Iwamura and by Miller, respectively) have been used extensively to obtain molecule-based magnets. The combination of these two kinds of magnetic molecular components has also been successfully explored to design polymeric magnets of different dimensionalities (the metal-radical approach). In this last case, both components play a magnetic role. A step forward in achieving multifunctionality is to design hybrid molecular materials formed by two independent molecular networks, such as anion/cation salts or host/guest solids, whereby each network furnishes distinct physical properties to the solid. This novel class of materials is interesting because it can give rise to the development of materials in which two properties in the same crystal lattice coexist, or materials that exhibit improved properties over those of the individual networks, or to new, unexpected properties due to the mutual interactions between them. One can imagine, for example, the combination of an extended inorganic magnetic layer opening the pathway to cooperative magnetism, with an organic or organometallic molecule that acts as a structural component controlling the interlayer separation. If the molecule inserted between the layers has unpaired electrons, a hybrid compound is produced that combines cooperative magnetism and paramagnetism. Other suitable combinations, such as electronic conductivity and magnetism, or nonlinear optics and magnetism, can also be achieved by wisely choosing the constituent molecules. In this article, we report some relevant examples that illustrate the potential of this hybrid approach in the context of molecule-based magnetic materials.

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Veciana, Jaume, i Hiizu Iwamura. "Organic Magnets". MRS Bulletin 25, nr 11 (listopad 2000): 41–51. http://dx.doi.org/10.1557/mrs2000.223.

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The notion of organic molecular materials showing metallic properties, such as electric conductivity or ferromagnetism, started several decades ago as a mere dream of some members of the chemical community. The goal was to create an assembly of organic molecules or macromolecules containing only light elements (C, H, N, O, S, etc.) and yet possessing the electron/hole mobility or spin alignment that is inherent in typical metals or their oxides and different from the isolated molecular materials. Organic molecular conductors initially were developed during the 1960s, but the first examples of organic molecular magnets took several more decades to be discovered, owing to the more subtle and complex structural and electronic aspects of these materials. The flurry of activity in this field can be traced to the widely held belief that even the most sophisticated properties can be rationally designed by a systematic modification of organic molecular structures. This motivation was further fueled by increased synthetic capabilities, especially for obtaining large organic molecules with suitable structures and topologies, and also by the spectacular progress of supramolecular chemistry for materials development witnessed in recent years. Also noteworthy is the pioneering work performed in the 1960s by several physical organic chemists who unraveled different ways of aligning spins within open-shell molecules (i.e., triplet diradicals, carbenes, etc.), working against nature's tendency to align them in an antiparallel manner. Magnetic interactions between unpaired electrons, located on the singly occupied molecular orbitals (SOMOs) of di- and polyradicals, or between the adjacent open-shell molecules in crystals, are a crucial issue in this evolving field. Thus, depending upon the symmetry, degeneracy,and topological characteristics of SOMOs and also on the mode of arrangement of the molecules in a crystal, the resulting interaction can align the neighboring spins parallel or antiparallel (see the introductory article by Miller and Epstein in this issue of MRS Bulletin).

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DE LA VENTA, J., E. FERNANDEZ PINEL, M. A. GARCIA, P. CRESPO, A. HERNANDO, O. RODRIGUEZ DE LA FUENTE, C. DE JULIÁN FERNÁNDEZ, A. FERNÁNDEZ i S. PENADÉS. "MAGNETIC PROPERTIES OF ORGANIC COATED GOLD SURFACES". Modern Physics Letters B 21, nr 06 (10.03.2007): 303–19. http://dx.doi.org/10.1142/s0217984907012761.

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We review here our recent results of experimental observation of room temperature magnetism in gold nanoparticles (NPs) and thin films. Capping gold surfaces with certain organic molecules leads to the appearance of magnetism at room temperature. The surface bonds between the organic molecules and Au atoms give rise to magnetic moments. These magnetic moments are blocked along the bond direction showing huge anisotropy. In the case of atomically flat surfaces, the magnetic moments are giants. An explanation of this orbital ferromagnetism is given. These results point out the possibility to observe magnetism at nanoscale in materials without typical magnetic atoms (transition metals and rare earths), and are of fundamental value to understand the magnetic properties of surfaces.

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Rajca, Andrzej. "From High-Spin Organic Molecules to Organic Polymers with Magnetic Ordering". Chemistry - A European Journal 8, nr 21 (4.11.2002): 4834–41. http://dx.doi.org/10.1002/1521-3765(20021104)8:21<4834::aid-chem4834>3.0.co;2-e.

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Kudisch, Bryan, Margherita Maiuri, Luca Moretti, Maria B. Oviedo, Leon Wang, Daniel G. Oblinsky, Robert K. Prud’homme, Bryan M. Wong, Stephen A. McGill i Gregory D. Scholes. "Ring currents modulate optoelectronic properties of aromatic chromophores at 25 T". Proceedings of the National Academy of Sciences 117, nr 21 (8.05.2020): 11289–98. http://dx.doi.org/10.1073/pnas.1918148117.

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The properties of organic molecules can be influenced by magnetic fields, and these magnetic field effects are diverse. They range from inducing nuclear Zeeman splitting for structural determination in NMR spectroscopy to polaron Zeeman splitting organic spintronics and organic magnetoresistance. A pervasive magnetic field effect on an aromatic molecule is the aromatic ring current, which can be thought of as an induction of a circular current of π-electrons upon the application of a magnetic field perpendicular to the π-system of the molecule. While in NMR spectroscopy the effects of ring currents on the chemical shifts of nearby protons are relatively well understood, and even predictable, the consequences of these modified electronic states on the spectroscopy of molecules has remained unknown. In this work, we find that photophysical properties of model phthalocyanine compounds and their aggregates display clear magnetic field dependences up to 25 T, with the aggregates showing more drastic magnetic field sensitivities depending on the intermolecular interactions with the amplification of ring currents in stacked aggregates. These observations are consistent with ring currents measured in NMR spectroscopy and simulated in time-dependent density functional theory calculations of magnetic field-dependent phthalocyanine monomer and dimer absorption spectra. We propose that ring currents in organic semiconductors, which commonly comprise aromatic moieties, may present new opportunities for the understanding and exploitation of combined optical, electronic, and magnetic properties.

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Albani, Guglielmo, Alberto Calloni, Andrea Picone, Alberto Brambilla, Michele Capra, Alessandro Lodesani, Lamberto Duò, Marco Finazzi, Franco Ciccacci i Gianlorenzo Bussetti. "An In-Depth Assessment of the Electronic and Magnetic Properties of a Highly Ordered Hybrid Interface: The Case of Nickel Tetra-Phenyl-Porphyrins on Fe(001)–p(1 × 1)O". Micromachines 12, nr 2 (13.02.2021): 191. http://dx.doi.org/10.3390/mi12020191.

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In this paper we focus on the structural, electronic, and magnetic properties of Ni tetra-phenyl-porphyrins (NiTPP) grown on top of Fe(001)–p(1 × 1)O. Ordered thin films of metal TPP molecules are potentially interesting for organic electronic and spintronic applications, especially when they are coupled to a ferromagnetic substrate. Unfortunately, porphyrin layers deposited on top of ferromagnetic substrates do not generally show long-range order. In this work, we provide evidence of an ordered disposition of the organic film above the iron surface and we prove that the thin layer of iron oxide decouples the molecules from the substrate, thus preserving the molecular electronic features, especially the HOMO-LUMO gap, even when just a few organic layers are deposited. The effect of the exposure to molecular oxygen is also investigated and an increased robustness against oxidation with respect to the bare substrate is detected. Finally, we present our results for the magnetic analysis performed by spin resolved spectroscopy, finding a null magnetic coupling between the molecules and the substrate.

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RAMAN, KARTHIK V., NICOLAE ATODIRESEI i JAGADEESH S. MOODERA. "TAILORING FERROMAGNET–MOLECULE INTERFACES: TOWARDS MOLECULAR SPINTRONICS". SPIN 04, nr 02 (czerwiec 2014): 1440014. http://dx.doi.org/10.1142/s2010324714400141.

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Understanding the interaction of organic molecules adsorbed on magnetic surfaces has shown considerable progress in recent years. The creation of hybridized interface between carbon-based aromatic molecule and the magnetic surface is observed to give rise to new interface states with unique electronic and magnetic character. This study has opened up a molecular-design initiative to tailor the spin dependent electronic and magnetic functionalities of the hybrid interface. The purpose of this article is to provide a fundamental understanding of the spin-chemistry and spin-physics associated with the formation of such ferromagnet-molecule hybrid interfaces. We also discuss the recent progress in this field using state-of-the-art experiments and theoretical calculations with focus on the magnetic properties of the molecule and the magnetic surface. The study reveals several interesting interface phenomena: formation of induced molecular moment and exchange coupling with the magnetic surface, and molecular spin-filters. It also demonstrates significant changes in the magnetic anisotropy and inter-atomic magnetic exchange coupling of the magnetic surface. These studies open the possibilities of exploring new molecular functionalities toward further research in the subfield of interface-assisted molecular spintronics.

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Sukenik, Nir, Francesco Tassinari, Shira Yochelis, Oded Millo, Lech Tomasz Baczewski i Yossi Paltiel. "Correlation between Ferromagnetic Layer Easy Axis and the Tilt Angle of Self Assembled Chiral Molecules". Molecules 25, nr 24 (20.12.2020): 6036. http://dx.doi.org/10.3390/molecules25246036.

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The spin–spin interactions between chiral molecules and ferromagnetic metals were found to be strongly affected by the chiral induced spin selectivity effect. Previous works unraveled two complementary phenomena: magnetization reorientation of ferromagnetic thin film upon adsorption of chiral molecules and different interaction rate of opposite enantiomers with a magnetic substrate. These phenomena were all observed when the easy axis of the ferromagnet was out of plane. In this work, the effects of the ferromagnetic easy axis direction, on both the chiral molecular monolayer tilt angle and the magnetization reorientation of the magnetic substrate, are studied using magnetic force microscopy. We have also studied the effect of an applied external magnetic field during the adsorption process. Our results show a clear correlation between the ferromagnetic layer easy axis direction and the tilt angle of the bonded molecules. This tilt angle was found to be larger for an in plane easy axis as compared to an out of plane easy axis. Adsorption under external magnetic field shows that magnetization reorientation occurs also after the adsorption event. These findings show that the interaction between chiral molecules and ferromagnetic layers stabilizes the magnetic reorientation, even after the adsorption, and strongly depends on the anisotropy of the magnetic substrate. This unique behavior is important for developing enantiomer separation techniques using magnetic substrates.

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Wang, Zengyao, Hao Wu, Qingyun Wu, Yi-Ming Zhao i Lei Shen. "Magnetic ε-Phosphorene for Sensing Greenhouse Gas Molecules". Molecules 28, nr 14 (14.07.2023): 5402. http://dx.doi.org/10.3390/molecules28145402.

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It is critical for gas sensors that sense greenhouse gas molecules to have both good sensitivity and selectivity for water molecules in the ambient environment. Here, we study the charge transfer, IV curves, and electric field tuning of vanadium-doped monolayer ϵ-phosphorene as a sensor for NO, NO2, and H2O gas molecules via first-principle and transport calculations. We find that the paramagnetic toxic molecules of NO and NO2 have a high adsorption energy on V-ϵ-phosphorene, which originates from a large amount of charge transfer driven by the hybridisation of the localised spin states of the host with the molecular frontier orbital. Using the non-equilibrium Green’s function, we investigate the IV responses with respect to the adsorption of different molecules to study the performance of gas molecule sensors. Our IV curves show a larger amount of changes in resistance of the paramagnetic NO and NO2 than nonmagnetic H2O gas molecules, suggesting both sensitivity and selectivity. Moreover, our calculations show that an applied external electric field (gate voltage) can effectively tune the amount of charge transfer. More charge transfer makes the sensor more sensitive to the molecule, while less charge transfer can reduce the adsorption energy and remove the adsorbed molecules, allowing for the repeated use of the sensor.

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Paez-Sierra, Beynor Antonio, Fredy Mesa i Anderson Dussan. "Raman Analysis of Vanadyl Phthalocynine Layers for Plastic Electronic Applications". Applied Mechanics and Materials 789-790 (wrzesień 2015): 170–75. http://dx.doi.org/10.4028/www.scientific.net/amm.789-790.170.

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Engineering, stability and orientation of semiconducting molecules are necessary to achieve the high efficiency of multifunctional organic-based devices. Several conjugated molecules facilitate the use of external magnetic fields to tailor both their molecular orientation and electronic properties while being processed for bio or opto-electronic applications. In this work, molecular thin films of vanadyl phthalocynine (VOPc) layers forming conducting channels in organic field-effect transistors were investigated. Three systems based on 100 nm thick VOPc thin film were grown, one in absence of magnetic field, while the other two with parallel and perpendicular to the substrate plane, respectively. Devices were ex-situ investigated by electrical characterization and confocal scanning Raman spectroscopy (SRS). All molecular layers growth on Au electrodes presented enhancement of the Raman signal.

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Ito, Akihiro, Masashi Urabe i Kazuyoshi Tanaka. "Design of high-spin organic molecules: toward magnetic parts in molecular electronics". Current Applied Physics 3, nr 2-3 (kwiecień 2003): 149–53. http://dx.doi.org/10.1016/s1567-1739(02)00193-1.

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Atodiresei, Nicolae, Vasile Caciuc i Predrag Lazić. "A Short Review on the Magnetic Effects Occurring at Organic Ferromagnetic Interfaces Formed between Benzene-Like Molecules and Graphene with Ferromagnetic Surfaces". Zeitschrift für Naturforschung A 69, nr 7 (1.07.2014): 360–70. http://dx.doi.org/10.5560/zna.2014-0026.

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In this article, we briefly summarize our results gained from recent density functional theory simulations aimed to investigate the interaction between organic materials containing π-electrons (i. e., several benzene-like molecules and graphene) with ferromagnetic surfaces. We show how the strong hybridization between the pz-electrons that initially form the π molecular orbitals with the magnetic d-states of the metal influences the spin polarization, the magnetic exchange coupling, and the magnetization direction at hybrid organic-ferromagnetic interface. From a practical perspective, these properties play a very important role for device applications based on organic materials and magnetic surfaces.

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Zhang, Lina, Shuyan Guan, Yunchang Fan, Chenxia Du, Dan Zhao i Baozhong Liu. "Towards solvent tuning of slow magnetic relaxation and ferroelectric properties in a dysprosium metal–organic framework system". Zeitschrift für Kristallographie - Crystalline Materials 234, nr 1 (28.01.2019): 33–41. http://dx.doi.org/10.1515/zkri-2018-2050.

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Abstract A new dysprosium metal–organic framework {[Dy2(L)3(H2O)4]·(acetone)2·(H2O)3}n (Dy2-Acetone) with single-molecule magnet and ferroelectric properties was synthesized through a solvent-induced single-crystal-to-single-crystal (SCSC) transformation. Notably, exchange of the coordinated and guest solvent molecules lead to different magnetic relaxation and ferroelectric properties in the dysprosium MOF system, Dy2-DMF and Dy2-Acetone. Study reveals that the tunable magnetic relaxation behaviors are most likely a result of different local coordination sphere and lattice solvent molecules within the pores which influenced and tuned the relaxation rates of the magnetization. Moreover, disparate polar solvent molecules confined in the MOFs may be the key factors for their different ferroelectric properties.

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de Jong, Michel P. "Recent progress in organic spintronics". Open Physics 14, nr 1 (1.01.2016): 337–53. http://dx.doi.org/10.1515/phys-2016-0039.

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AbstractThe field of organic spintronics deals with spin dependent phenomena occurring in organic semiconductors or hybrid inorganic/organic systems that may be exploited for future electronic applications. This includes magnetic field effects on charge transport and luminescence in organic semiconductors, spin valve action in devices comprising organic spacers, and magnetic effects that are unique to hybrid interfaces between (ferromagnetic) metals and organic molecules. A brief overview of the current state of affairs in the field is presented.

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Pan, Haiyang, Xiaobo Wang, Qiaoming Wang, Xiaohua Wu, Chang Liu, Nian Lin i Yue Zhao. "Proximity Effect of Epitaxial Iron Phthalocyanine Molecules on High-Quality Graphene Devices". Chinese Physics Letters 38, nr 8 (1.09.2021): 087201. http://dx.doi.org/10.1088/0256-307x/38/8/087201.

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Depositing magnetic insulators on graphene has been a promising route to introduce magnetism via exchange proximity interaction in graphene for future spintronics applications. Molecule-based magnets may offer unique opportunities because of their synthesis versatility. Here, we investigate the magnetic proximity effect of epitaxial iron phthalocyanine (FePc) molecules on high-quality monolayer and bilayer graphene devices on hexagonal boron nitride substrates by probing the local and nonlocal transport. Although the FePc molecules introduce large hole doping effects combined with mobility degradation, the magnetic proximity gives rise to a canted antiferromagnetic state under a magnetic field in the monolayer graphene. On bilayer graphene and FePc heterostructure devices, the nonlocal transport reveals a pronounced Zeeman spin-Hall effect. Further analysis of the scattering mechanism in the bilayer shows a dominated long-range scattering. Our findings in graphene/organic magnetic insulator heterostructure provide a new insight for use of molecule-based magnets in two-dimensional spintronic devices.

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Epstein, Arthur J. "Organic-Based Magnets: Opportunities in Photoinduced Magnetism, Spintronics, Fractal Magnetism, and Beyond". MRS Bulletin 28, nr 7 (lipiec 2003): 492–99. http://dx.doi.org/10.1557/mrs2003.145.

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AbstractThis article is based on a presentation on organic-based magnets given as part of Symposium X—Frontiers of Materials Research on December 4, 2002, at the 2002 Materials Research Society Fall Meeting in Boston. The advent of organic-based magnets opened the opportunity for tuning magnetic properties by molecular design and the discovery of new phenomena that rely on the internal structure of the molecules that make up these magnets. In the past 18 years, numerous classes of organic-based ferromagnets, ferrimagnets, and spin glasses (spins essentially frozen in place without long-range order) have been reported. These materials have magnetic ordering temperatures ranging from <1 K to above room temperature and demonstrate many of the magnetic properties associated with conventional magnets. This article concentrates on new phenomena that are unique to organic-based magnets. Three of these effects—“high-temperature” light-induced magnetism, spin-polarized magnetic organic semiconductors with the potential for spintronics, and the development of fractal magnetic order—are discussed to illustrate the richness of opportunity in organic-based magnets.

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Elmanakhly, Mohammed Imam, Marko George Rizk i Shaaban Mohamed Ghazy Oreif Eslam. "Research on the importance of NMR technology in medicine and other fields". Glavvrač (Chief Medical Officer), nr 1 (2022): 28–42. http://dx.doi.org/10.33920/med-03-2201-04.

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Nuclear magnetic resonance (NMR) spectroscopy was invented and developed over six decades ago as an integral part of the chemical and structural analysis of small molecules, polymers, biomaterials and hybrids. High-resolution nuclear magnetic resonance (NMR) spectroscopy plays a special role. Nuclear magnetic resonance methods are mainly used for the structural analysis of synthetic and biosynthetic organic and organic compounds and natural products, as well as for the identification of one or more components in complex matrices. Nuclear magnetic resonance spectroscopy is also one of the most powerful analytical tools for the qualitative and quantitative analysis in biological fluids of low-molecular-weight autotrophic metabolites produced by medicines and narcotic drugs. There is a growing trend towards the use of high-resolution NMR spectroscopy in food science. In this context, we will focus on the importance of NMR spectroscopy for studying low-molecular-weight organic materials using selected examples. High-resolution nuclear magnetic resonance (NMR) spectroscopy plays a special role.

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Lambruschini, Chiara, Silvia Villa, Luca Banfi, Fabio Canepa, Fabio Morana, Annalisa Relini, Paola Riani, Renata Riva i Fulvio Silvetti. "Enzymatically promoted release of organic molecules linked to magnetic nanoparticles". Beilstein Journal of Nanotechnology 9 (27.03.2018): 986–99. http://dx.doi.org/10.3762/bjnano.9.92.

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Magnetite-based magnetic nanoparticles have been successfully coupled to an organic system constituted of a fluorescent molecule, a tripeptide specifier and a spacer. The system is able to selectively release the fluorescent molecule upon targeted enzymatic hydrolysis promoted by a lysine/arginine specific protease.

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Naaman, Ron, i Zeev Vager. "Cooperative Electronic and Magnetic Properties of Self-Assembled Monolayers". MRS Bulletin 35, nr 6 (czerwiec 2010): 429–34. http://dx.doi.org/10.1557/mrs2010.580.

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AbstractSelf-assembled monolayers (SAMs) of organic dipolar molecules have new electronic and magnetic properties that result from their organization, despite the relatively weak interaction among the molecules themselves. Here we review the origin of this cooperative effect and summarize work performed on spin selective electron transmission through SAMs. The spin selectivity observed, in some cases, is consistent with a model in which a SAM containing chiral dipolar molecules behaves like a magnetic layer. The magnetic properties result in the SAMs behaving as spin filters, even without applying an external magnetic field to the layer.

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Imai, Yoshitane. "Generation of Circularly Polarized Luminescence by Symmetry Breaking". Symmetry 12, nr 11 (28.10.2020): 1786. http://dx.doi.org/10.3390/sym12111786.

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Circularly polarized luminescence (CPL) has attracted significant attention in the fields of chiral photonic science and optoelectronic materials science. In a CPL-emitting system, a chiral luminophore derived from chiral molecules is usually essential. In this review, three non-classical CPL (NC-CPL) systems that do not use enantiomerically pure molecules are reported: (i) supramolecular organic luminophores composed of achiral organic molecules that can emit CPL without the use of any chiral auxiliaries, (ii) achiral or racemic luminophores that can emit magnetic CPL (MCPL) by applying an external magnetic field of 1.6 T, and (iii) circular dichroism-silent organic luminophores that can emit CPL in the photoexcited state as a cryptochiral CPL system.

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Awaga, Kunio, Wataru Fujita, Taketoshi Sekine i Tsunehisa Okuno. "Intercalation of Functional Organic Molecules Into Copper(II) Magnetic Materials". Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals 286, nr 1 (lipiec 1996): 1–8. http://dx.doi.org/10.1080/10587259608042257.

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Falck, D., i W. M. A. Niessen. "Solution-phase electrochemistry-nuclear magnetic resonance of small organic molecules". TrAC Trends in Analytical Chemistry 70 (lipiec 2015): 31–39. http://dx.doi.org/10.1016/j.trac.2015.03.010.

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Kucherenko, M. G. "SPIN-SELECTIVE INTERACTION OF TRIPLET-EXCITED MOLECULES ON THE SURFACE OF A FERROMAGNETIC NANOPARTICLE". Eurasian Physical Technical Journal 19, nr 4 (26.12.2022): 5–16. http://dx.doi.org/10.31489/2022no4/5-16.

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Influence of a magnetic field generated by a ferromagnetic nanoparticle on the annihilation of triplet-excited organic molecules or triplet excitons in a near-surface particle layer is studied. A detailed mathematical model is presented that accounts for electron excitation diffusive mobility and geometry of the system. The kinetic operator is given in the complete 9x9 basis of triplet- triplet pair spin states. Time dependencies of the singlet spin state population of the triplet-triplet pair and the dependence of the triplet-triplet annihilation magnetic response profile (magnetic reaction effect) from the magnetic field induction are obtained. It is found that the influence of a magnetic field gradient on the reaction yield dominates over the other known mechanisms of spin-dynamics in triplet- triplet pairs.

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Dahal, Bishnu R., Andrew Grizzle, Christopher D’Angelo, Vincent Lamberti i Pawan Tyagi. "Competing Easy-Axis Anisotropies Impacting Magnetic Tunnel Junction-Based Molecular Spintronics Devices (MTJMSDs)". International Journal of Molecular Sciences 23, nr 22 (21.11.2022): 14476. http://dx.doi.org/10.3390/ijms232214476.

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Molecular spintronics devices (MSDs) attempt to harness molecules’ quantum state, size, and configurable attributes for application in computer devices—a quest that began more than 70 years ago. In the vast number of theoretical studies and limited experimental attempts, MSDs have been found to be suitable for application in memory devices and futuristic quantum computers. MSDs have recently also exhibited intriguing spin photovoltaic-like phenomena, signaling their potential application in cost-effective and novel solar cell technologies. The molecular spintronics field’s major challenge is the lack of mass-fabrication methods producing robust magnetic molecule connections with magnetic electrodes of different anisotropies. Another main challenge is the limitations of conventional theoretical methods for understanding experimental results and designing new devices. Magnetic tunnel junction-based molecular spintronics devices (MTJMSDs) are designed by covalently connecting paramagnetic molecules across an insulating tunneling barrier. The insulating tunneling barrier serves as a mechanical spacer between two ferromagnetic (FM) electrodes of tailorable magnetic anisotropies to allow molecules to undergo many intriguing phenomena. Our experimental studies showed that the paramagnetic molecules could produce strong antiferromagnetic coupling between two FM electrodes, leading to a dramatic large-scale impact on the magnetic electrode itself. Recently, we showed that the Monte Carlo Simulation (MCS) was effective in providing plausible insights into the observation of unusual magnetic domains based on the role of single easy-axis magnetic anisotropy. Here, we experimentally show that the response of a paramagnetic molecule is dramatically different when connected to FM electrodes of different easy-axis anisotropies. Motivated by our experimental studies, here, we report on an MCS study investigating the impact of the simultaneous presence of two easy-axis anisotropies on MTJMSD equilibrium properties. In-plane easy-axis anisotropy produced multiple magnetic phases of opposite spins. The multiple magnetic phases vanished at higher thermal energy, but the MTJMSD still maintained a higher magnetic moment because of anisotropy. The out-of-plane easy-axis anisotropy caused a dominant magnetic phase in the FM electrode rather than multiple magnetic phases. The simultaneous application of equal-magnitude in-plane and out-of-plane easy-axis anisotropies on the same electrode negated the anisotropy effect. Our experimental and MCS study provides insights for designing and understanding new spintronics-based devices.

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Tian, Qipeng, i Shijie Xie. "Spin Injection and Transport in Organic Materials". Micromachines 10, nr 9 (10.09.2019): 596. http://dx.doi.org/10.3390/mi10090596.

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This review introduces some important spin phenomena of organic molecules and solids and their devices: Organic spin injection and transport, organic spin valves, organic magnetic field effects, organic excited ferromagnetism, organic spin currents, etc. We summarize the experimental and theoretical progress of organic spintronics in recent years and give prospects.

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Campo, Javier, Javier Luzon, Laura Cañadillas, Naoki Amaya, Fernando Palacio i Yuko Hosokoshi. "Purely organic magnets: How to get ferromagnetic interactions". Acta Crystallographica Section A Foundations and Advances 70, a1 (5.08.2014): C1085. http://dx.doi.org/10.1107/s2053273314089141.

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Purely organic magnets, materials with spontaneous magnetization despite no containing magnetic ions, are very promising for technological applications due to their peculiar properties as flexibility, lightness or even biocompatibility. Most of the published purely organic magnets are free radical compounds. One of the most important difficulties in order to get spontaneous magnetization in such materials is that magnetic interactions among free radicals are usually antiferromagnetic and, in addition, ferromagnetic interactions are weaker than the antiferromagnetic ones. A possible strategy to overcome this issue is the use of triradical molecules with total spin S=1/2. In this case, an adequate packing of the triradical molecules can give place to antiferromagnetic interactions between regions with positive spin density and regions with negative spin density of two close molecules. This antiferromagnetic interaction between regions with opposite spin density would result in an overall ferromagnetic interaction between the two close triradicals. With this idea in mind we have performed an study of the spin density distribution and of the intramolecular and intermolecular magnetic interactions of the triradical compound 2-[3',5'-bis(Ntert-butylaminoxyl)phenyl]-4,4,5,5-tetramethyl-4,5-dihydro-1-Himidazol-1-oxyl-3-oxide, containing two N-tert-butyl aminoxyls and a nitronyl nitroxide groups. Combination of experimental data from a polarized neutron diffraction experiment and ab initio calculations (DFT) has allowed us to obtain the spin density distribution. In addition, the intramolecular and intermolecular magnetic interactions have been computed by ab initio quantum chemistry methods. The values for the intramolecular interactions confirm the S=1/2 ground state of the triradical. As for the intermolecular interactions, the two strongest ones are ferromagnetic, what is in agreement with the overlapping of regions with opposite spin density of the two interacting triradicals. These results support the strategy of using triradical molecules for obtaining purely organic magnets with higher magnetic transition ordering temperatures since is easier to obtain ferromagnetic interactions between the radicals and these interactions, having an antiferromagnetic origin, can be stronger than typical ferromagnetic interactions between radicals.

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Mínguez Espallargas, Guillermo, Mónica Giménez-Marqués, Néstor Calvo Galve i Eugenio Coronado. "Responsive magnetic coordination polymers: effects of gas sorption". Acta Crystallographica Section A Foundations and Advances 70, a1 (5.08.2014): C905. http://dx.doi.org/10.1107/s2053273314090949.

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Responsive materials for which physical or chemical properties can be tuned by applying an external stimulus are attracting considerable interest in view of their potential applications as chemical switches or molecular sensors [1]. A major source of such materials is provided by the so-called metal-organic frameworks (MOFs), in which physisorption of guest molecules, located in the pores, can cause subtle changes which affect the magnetic properties. Here we present two different approaches to modify the magnetic properties through gas sorption. First, we show that the chemisorption of gaseous HCl molecules by a non-porous one-dimensional coordination polymer instigates drastic modifications in the magnetic properties of the material, switching from strong antiferromagnets to ferromagnets upon gas sorption [2]. These conversions result from profound structural changes, involving cleavage and formation of covalent bonds caused by the removal/addition of ligands from the framework itself, but with no disruption of crystallinity. In a different approach, we present a family of FeII coordination polymers which shows spin-crossover behaviour and selectively sorbs CO2 over N2 [3]. Despite the lack of permanent channels, these non-porous coordination polymers trap CO2 gas molecules into the internal cavities due to the flexible and dynamic nature of the framework. One CO2 molecule is incorporated in each internal cavity of the crystalline material, as unequivocally demonstrated by structural determination after CO2 loading. This physisorption shifts the spin transition producing an increase in the transition temperature of 9 K (see Figure).

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Yan, Hong Yuan, Zhao Li, Tian Hui Hu i Ye Hong Han. "Preparation and Characteristic of the New Magnetic Organic–Inorganic Hybrid Molecularly Imprinted Microsphere Materials". Applied Mechanics and Materials 184-185 (czerwiec 2012): 1106–9. http://dx.doi.org/10.4028/www.scientific.net/amm.184-185.1106.

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The new magnetic organic–inorganic hybrid composite imprinted microspheres (MHCIM) based on Fe3O4 nanospheres as core structure and imprinted materials as shell structure have been synthesized by surface molecularly imprinted technique using dummy template strategy. Scanning electron microscopy images showed that the MHCIM were with a diameter distribution (10-120 µm) and cross-linking, spherical shape, and porous morphologies. The resultant MHCIM incorporating molecular recognition and magnetic separation properties can provide a highly selective absorbent materials for trace extraction and isolation target molecules from complicated biological matrix.

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LIN, TIEN-SUNG, DAVID J. SLOOP i CHUNG-YUAN MOU. "UTILIZATION OF POLARIZED ELECTRON SPIN OF ORGANIC MOLECULES IN QUANTUM COMPUTING". International Journal of Quantum Information 03, supp01 (listopad 2005): 205–13. http://dx.doi.org/10.1142/s0219749905001389.

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The possibility of utilizing highly polarized electron spin of the photo-excited triplet state of organic semiconductors (pentacene molecules) embedded in organic crystals and mesoporous materials by zero-field (ZF) and near zero-field (NZF) pulsed electron paramagnetic resonance (EPR) techniques in a quantum computer will be explored. A simple logic gate, such as CNOT, utilizing such highly polarized electron spins communicating with the surrounding paramagnetic nuclei via hyperfine interaction will be discussed. Major advantages of these approaches are: (1) high electron spin polarization, (2) possible single-molecule detection, (3) orchestrated quantum perturbations can be imposed, and (4) pulsed ZF and NZF EPR techniques can be performed without high magnetic field.

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Calloni, Alberto, Madan S. Jagadeesh, Guglielmo Albani, Claudio Goletti, Lamberto Duò, Franco Ciccacci i Gianlorenzo Bussetti. "Ordered assembling of Co tetra phenyl porphyrin on oxygen-passivated Fe(001): from single to multilayer films". EPJ Web of Conferences 230 (2020): 00014. http://dx.doi.org/10.1051/epjconf/202023000014.

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Tetra-phenyl prophyrins (TPP) are an interesting class of organic molecules characterized by a ring structure with a metal ion in their centre. An ordered growth of such molecules can be obtained even on metallic substrates by means of a proper modification of the reactive interface, as we demonstrated for ZnTPP molecules coupled to oxygen-passivated Fe(001) [G. Bussetti et al. Appl. Surf. Sci. 390, 856 (2016)]. More recently, we focused on CoTPP molecules, characterized by a not nil magnetic moment and therefore of potential interest for magnetic applications. As in the ZnTPP case, our results for one monolayer coverage report the formation of an ordered assembly of flat-lying molecules. However, some differences between the two molecular species are observed in the packing scheme and in the degree of electronic interaction with the substrate. With the aim of reaching, also for CoTPP, a comprehensive view of molecular organization on Fe, we complement here our previous investigations by following the growth of the CoTPP film for increasing coverage, showing that an ordered stacking of such molecules is indeed realized at least up to four molecular layers.

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Li, Xu. "Organic Photochromic Radical Compound Based on a Biindenylidene System". Journal of Chemical Research 2008, nr 10 (październik 2008): 598–600. http://dx.doi.org/10.3184/030823408x360300.

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A novel dual functional biindenylidene derivative (4) having nitronyl nitroxide radicals on both sides of the molecules, was synthesised. Its photochromism, as well as magnetic properties were investigated. The compound 4 underwent photochromic reactions by irradiation with UV and visible light. The intermolecular magnetic interactions were measured with a SQUID susceptometer.

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32

Wan, Qingyun, Masanori Wakizaka, Haitao Zhang, Yongbing Shen, Nobuto Funakoshi, Chi-Ming Che, Shinya Takaishi i Masahiro Yamashita. "A New Organic Conductor of Tetramethyltetraselenafulvalene (TMTSF) with a Magnetic Dy(III) Complex". Magnetochemistry 9, nr 3 (6.03.2023): 77. http://dx.doi.org/10.3390/magnetochemistry9030077.

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A new molecular conductor of (TMTSF)5[Dy(NCS)4(NO3)2]CHCl3 was prepared using the electrochemical oxidation method. The complex crystallizes in the Cmc21 (36) space group, where the partially-oxidized TMTSF molecules form a 1D (one-dimensional) column structure. The crystal shows a semiconducting behavior with a room temperature conductivity of 0.2 S·cm−1 and an activation energy of 34 meV at ambient pressure.

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33

Podunavac-Kuzmanovic, Sanja, i Ljiljana Vojinovic. "Synthesis and physico-chemical characterization of zinc(II), nickel(II) and cobalt(II) complexes with 2-phenyl-2-imidazoline". Acta Periodica Technologica, nr 34 (2003): 119–24. http://dx.doi.org/10.2298/apt0334119p.

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Chlorides and nitrates of zinc(II), nickel(II) and cobalt(II) react with 2-phenyl-2-imidazoline to give complexes of the type [ML2X2]?nH2O (M=Zn, Ni or Co; L=2-phenyl-2-imidazoline; X=Cl or NO3; n=0, 1 or 2). The complexes were synthesized and characterized by elemental analysis of the metal molar conductivity, magnetic susceptibility measurements and IR spectra. The molar conductances of the zinc(II) complexes in DMF solutions indicate that the complexes behave as non-electrolytes. The values of magnetic conductivity in the case of nickel(II) complexes indicate that one of the coordinated anions (chloride or nitrate) has been replaced by DMF molecule. The molar conductivity values of cobalt(II) complexes indicate the partial substitution of coordinated anions with solvent molecules. The room temperature effective magnetic moments and IR data of the complexes suggest that all Zn(II), Ni(II) and Co(II) complexes have a tetrahedral configuration, which is realized by participation of the pyridine nitrogen of two organic ligand molecules, and two chloride or nitrate anions typical for these classes of organic ligands.

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Tamulis, Arvydas, Vykintas Tamulis i Aiste Ziriakoviene. "Quantum Mechanical Design of Molecular Computers Elements Suitable for Self-Assembling to Quantum Computing Living Systems". Solid State Phenomena 97-98 (kwiecień 2004): 173–80. http://dx.doi.org/10.4028/www.scientific.net/ssp.97-98.173.

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There are presented logic gates of molecular electronics digital computers. Maximal length of these molecular electronics digital logic gates are no more than four nanometers and maximal width 2.5 nm. The results of light induced internal molecular motions in azo-dyes molecules have been used for the design of light driven logically controlled (OR, AND) molecular machines composed from organic photoactive electron donor dithieno[3,2-b:2',3'-d]thiophene and ferrocene molecules, electron accepting tetracyano-indane molecule, and moving azo-benzene molecular fragment. Density functional theory (DFT) B3PW91/6-311G model calculations were performed for the geometry optimization of these molecular electronics logical gates. Applied DFT time dependent (DFT-TD/B3PW91) method and our visualization program give absorption spectra of designed molecular gates and show from which fragments electrons are hopping in various excited states. Quantum mechanical investigations of proton Nuclear Magnetic Resonance (NMR) values of Cu, Co, Zn, Mn and Fe biliverdin derivatives and their dimers using ab initio Hartree-Fock (HF) and DFT methods indicate that these modified derivatives should generate from one to twelve Quantum Bits (QuBits). The chemical shifts are obtained as the difference of the values of the tetramethylsilane (Si(CH3)4) molecule Gauge-Independent Atomic Orbital (GIAO) nuclear magnetic shielding tensor on the hydrogen atoms and that of the magnetically active molecules. There are designed several single supermolecule and supramolecular devices containing molecular electronics digital logic gates, photoactive molecular machines and elements of molecular NMR quantum computers that allowed to design several supramolecular Control NOT NMR quantum computing gates. Self-assembling simulations of these molecular quantum computing gates induced idea of self-assembled molecular quantum supercomputer and molecular quantum computing life.

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Dougherty, Dennis A., i David A. Kaisaki. "New Designs for Organic Molecules and Materials with Novel Magnetic Properties". Molecular Crystals and Liquid Crystals Incorporating Nonlinear Optics 183, nr 1 (styczeń 1990): 71–79. http://dx.doi.org/10.1080/15421409008047442.

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Wei, Wei, Fu-quan Bai, Bao-hui Xia, Hai-bo Chen i Hong-xing Zhang. "Theoretical analysis on magnetic properties of conjugated organic molecules containing borepin". Chemical Research in Chinese Universities 29, nr 5 (14.09.2013): 962–68. http://dx.doi.org/10.1007/s40242-013-3129-0.

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Zhu, L., K. L. Yao i Z. L. Liu. "Biradical and triradical organic magnetic molecules as spin filters and rectifiers". Chemical Physics 397 (marzec 2012): 1–8. http://dx.doi.org/10.1016/j.chemphys.2011.09.009.

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Sarbadhikary, Prodipta, Suranjan Shil, Anirban Panda i Anirban Misra. "A Perspective on Designing Chiral Organic Magnetic Molecules with Unusual Behavior in Magnetic Exchange Coupling". Journal of Organic Chemistry 81, nr 13 (20.06.2016): 5623–30. http://dx.doi.org/10.1021/acs.joc.6b00943.

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Urusov, Alexandr E., Alina V. Petrakova, Anatoly V. Zherdev i Boris B. Dzantiev. "Magnetic Nanopartices as Carriers for Immunoassays". Nano Hybrids and Composites 13 (styczeń 2017): 54–62. http://dx.doi.org/10.4028/www.scientific.net/nhc.13.54.

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Magnetic nanoparticles (MNP) are efficient molecular carriers for affine molecules. MNP complexes with antibodies can be used for the selective concentration and highly sensitive detection of various compounds. In this paper, development steps of the enzyme immunoassay using MNP are considered in details. Simple method of MNP synthesis and production of conjugates of antibodies with the aggregated MNP using physical sorption is presented. Simple, yet effective, formats of enzyme immunoassay are given. Using aflatoxin B1 detection as an example, possibility of decreasing detection limit up to 2 pg/mL, with a considerable decrease in the assay time, and performing immune interaction in the media with high organic content is shown.

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40

Lee, H. J., H. B. Cui, H. Fujiwara, H. Kobayashi, E. Fujiwara i A. Kobayashi. "Development of new magnetic organic conductors based on donor molecules with stable organic radical part". Journal de Physique IV (Proceedings) 114 (kwiecień 2004): 533–35. http://dx.doi.org/10.1051/jp4:2004114126.

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Keith, T. A., i R. F. W. Bader. "Properties of atoms in molecules: nuclear magnetic shielding". Canadian Journal of Chemistry 74, nr 2 (1.02.1996): 185–200. http://dx.doi.org/10.1139/v96-022.

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This paper analyzes the nuclear magnetic shielding tensors underlying the chemical shift in NMR spectroscopy in terms of the field generated at the nucleus by the current J(1)(r) induced by an external magnetic field. The magnetic field at nucleus [Formula: see text] resulting from an element of the induced current density at a distance [Formula: see text] is proportional to [Formula: see text] which defines the shielding density [Formula: see text] The magnetic shielding of a nucleus is fundamentally an atomic property, a feature brought to the fore by using the theory of atoms in molecules and the integration of [Formula: see text] over the individual atomic basins relates the shielding tensor [Formula: see text] to a sum of atomic contributions. The shielding of nucleus ** is primarily determined by the flow of current within the basin of atom [Formula: see text], a contribution that varies from the approximate diamagnetic limit, given by the atomic Lamb value for the atom in the molecule, to values that are greatly reduced by the presence of paramagnetic current flows associated with particular bonding effects. Whether the contribution of a neighbouring atom is shielding or deshielding is readily understood by relating the form of the current flow within its basin to the magnetization density. [Formula: see text]. A study of the currents induced in benzene shows that the extent to which a proton, bonded to a ring of atoms, is deshielded by the field exerted by its bonded neighbour provides a direct diagnostic test for a ring current and an accurate relative measure of its strength. The theory of atoms in molecules isolates transferable atomic properties and because of this ability one finds, in addition to the anticipated result that a given functional group contributes identical amounts to the isotropic shielding [Formula: see text] of a nucleus external to it through a series of molecules, the more remarkable result that the whole of the variation in [Formula: see text] can have its origin in the basin of atom [Formula: see text], the contribution from external groups remaining constant. For example, the external contribution to [Formula: see text] for a carbon nucleus in a normal hydrocarbon is independent of chain length and position of [Formula: see text] within the chain, the methyl group in ethane contributing the same shielding to a methyl carbon as does the butyl group in pentane. This constancy in external contributions to the shielding is also found for N, O and F nuclei in substituted, saturated hydrocarbons. Key words: NMR, magnetic shielding, current density, magnetic shielding density.

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Gao, Ling-Ling, Qian-Nan Zhao, Miao-Miao Li, Li-Ming Fan, Xiao-Yan Niu, Xiao-Qing Wang i Tuo-Ping Hu. "Magnetic properties and luminescence sensing of five coordination polymers based on a rigid terphenyl-tetracarboxylic acid". CrystEngComm 19, nr 44 (2017): 6651–59. http://dx.doi.org/10.1039/c7ce01510k.

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Jobelius, Hannah, Norbert Wagner, Gregor Schnakenburg i Andreas Meyer. "Verdazyls as Possible Building Blocks for Multifunctional Molecular Materials: A Case Study on 1,5-Diphenyl-3-(p-iodophenyl)-verdazyl Focusing on Magnetism, Electron Transfer and the Applicability of the Sonogashira-Hagihara Reaction". Molecules 23, nr 7 (18.07.2018): 1758. http://dx.doi.org/10.3390/molecules23071758.

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This work explores the use of Kuhn verdazyl radicals as building blocks in multifunctional molecular materials in an exemplary study, focusing on the magnetic and the electron transfer (ET) characteristics, but also addressing the question whether chemical modification by cross-coupling is possible. The ET in solution is studied spectroscopically, whereas solid state measurements afford information about the magnetic susceptibility or the conductivity of the given samples. The observed results are rationalized based on the chemical structures of the molecules, which have been obtained by X-ray crystallography. The crystallographically observed molecular structures as well as the interpretation based on the spectroscopic and physical measurements are backed up by DFT calculations. The measurements indicate that only weak, antiferromagnetic (AF) coupling is observed in Kuhn verdazyls owed to the low tendency to form face-to-face stacks, but also that steric reasons alone are not sufficient to explain this behavior. Furthermore, it is also demonstrated that ET reactions proceed rapidly in verdazyl/verdazylium redox couples and that Kuhn verdazyls are suited as donor molecules in ET reactions.

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Xiao Lixin, 肖立新, 胡双元 Hu Shuangyuan, 孔胜 Kong Sheng, 亓博远 Qi Boyuan, 张明骁 Zhang Mingxiao, 陈志坚 Chen Zhijian, 曲波 Qu Bo i 龚旗煌 Gong Qihuang. "Small Organic Molecules for Blue Electroluminescence". Acta Optica Sinica 30, nr 7 (2010): 1895–903. http://dx.doi.org/10.3788/aos20103007.1895.

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Kreifeldt, Erik. "Organic Molecules Trip Optical Switch". Optics and Photonics News 7, nr 7 (1.07.1996): 10. http://dx.doi.org/10.1364/opn.7.7.000010.

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Dressel, M., M. Dumm, T. Knoblauch, B. Köhler, B. Salameh i S. Yasin. "Charge Order Breaks Magnetic Symmetry in Molecular Quantum Spin Chains". Advances in Condensed Matter Physics 2012 (2012): 1–13. http://dx.doi.org/10.1155/2012/398721.

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Charge order affects most of the electronic properties but is believed not to alter the spin arrangement since the magnetic susceptibility remains unchanged. We present electron-spin-resonance experiments on quasi-one-dimensional(TMTTF)2Xsalts (X=PF6, AsF6, and SbF6), which reveal that the magnetic properties are modified belowTCOwhen electronic ferroelectricity sets in. The coupling of anions and organic molecules rotates the g-tensor out of the molecular plane creating magnetically nonequivalent sites on neighboring chains at domain walls. Due to anisotropic Zeeman interaction a novel magnetic interaction mechanism in the charge-ordered state is observed as a doubling of the rotational periodicity ofΔH.

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Zhang, Fengying, Zijun Zhang, Yali Zhao, Chao Du, Yong Li, Jiaqi Gao, Xiaobo Ren, Teng Ma, Boqiong Li i Yuxiang Bu. "Redox-Regulated Magnetic Conversions between Ferro- and Antiferromagnetism in Organic Nitroxide Diradicals". Molecules 28, nr 17 (24.08.2023): 6232. http://dx.doi.org/10.3390/molecules28176232.

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Redox-induced magnetic transformation in organic diradicals is an appealing phenomenon. In this study, we theoretically designed twelve couples of diradicals in which two nitroxide (NO) radical groups are connected to the redox-active couplers including p-benzoquinonyl, 1,4-naphthoquinyl, 9,10-anthraquinonyl, naphthacene-5,12-dione, pentacene-6,13-dione, hexacene-6,15-dione, pyrazinyl, quinoxalinyl, phenazinyl, 5,12-diazanaphthacene, 6,13-diazapentacene, and 6,15-diazahexacene. As evidenced at both the B3LYP and M06-2X levels of theory, the calculations reveal that the magnetic reversal can take place from ferromagnetism to antiferromagnetism, or vice versa, by means of redox method in these designed organic magnetic molecules. It was observed that p-benzoquinonyl, 1,4-naphthoquinyl, 9,10-anthraquinonyl, naphthacene-5,12-dione, pentacene-6,13-dione, and hexacene-6,15-dione-bridged NO diradicals produce antiferromagnetism while their dihydrogenated counterparts exhibit ferromagnetism. Similarly, pyrazinyl, quinoxalinyl, phenazinyl, 5,12-diazanaphthacene, 6,13-diazapentacene, and 6,15-diazahexacene-bridged NO diradicals present ferromagnetism while their dihydrogenated counterparts show antiferromagnetism. The differences in the magnetic behaviors and magnetic magnitudes of each of the twelve couples of diradicals could be attributed to their distinctly different spin-interacting pathways. It was found that the nature of the coupler and the length of the coupling path are important factors in controlling the magnitude of the magnetic exchange coupling constant J. Specifically, smaller HOMO-LUMO (HOMO: highest occupied molecular orbital, LUMO: lowest unoccupied molecular orbital) gaps of the couplers and shorter coupler lengths, as well as shorter linking bond lengths, can attain stronger magnetic interactions. In addition, a diradical with an extensively π-conjugated structure is beneficial to spin transport and can effectively promote magnetic coupling, yielding a large |J| accordingly. That is, a larger spin polarization can give rise to a stronger magnetic interaction. The sign of J for these studied diradicals can be predicted from the spin alternation rule, the shape of the singly occupied molecular orbitals (SOMOs), and the SOMO-SOMO energy gaps of the triplet state. This study paves the way for the rational design of magnetic molecular switches.

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Boughendjioua, Hicham, Nadia Amoura i Zahra Boughendjioua. "Purity Specifications of Constituents of Cinnamon Essential Oil by Fourier Transformed Infrared Spectroscopy Analysis". Indian Journal of Pharmaceutical and Biological Research 5, nr 02 (30.06.2017): 36–40. http://dx.doi.org/10.30750/ijpbr.5.2.7.

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Three main tools are used to determine the structures of organic molecules. These tools are infrared (IR) spectroscopy, mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy. Infrared Spectroscopy (IR), Mass Spectrometry (MS) and Nuclear Magnetic Resonance Spectroscopy (NMR). Organic molecules absorb light (infrared, ultraviolet, etc.) at particular wavelengths based on different vibrational modes unique to the specific functional groups and structural features. In the present study, the volatile compounds of Cinnamon (Cinnamomum zeylanicum) were detected and identified by Fourier Transformed Infrared Spectroscopy (FTIR) analysis. FTIR allowed us to identify 10 volatile compounds and indicated than the functional groups of the essential oils are CHx, C=C and C=O.

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JUN, WOONG GI, HYUK YOON, SEUNG HWAN LEE, JAE HONG KIM i DONG HOON CHOI. "INORGANIC–ORGANIC HYBRID PHOTOREFRACTIVE MATERIALS BEARING THE BIFUNCTIONAL CHROMOPHORE". Journal of Nonlinear Optical Physics & Materials 14, nr 04 (grudzień 2005): 497–504. http://dx.doi.org/10.1142/s0218863505002943.

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We prepared the photorefractive composite based on organic–inorganic hybrid materials containing charge-transporting molecules, second-order nonlinear optical chromophore, photosensitizer, and plasticizer either as a side chain unit or a guest molecule. New chromophore was synthesized to contain nonlinear optical chromophore and carbazole in one molecule. The functional chromophores were reacted to isocyanatotriethoxysilane to provide the functional precursor molecules. 2,4,7-Trinitrofluorenone (TNF) was added into the sol-gel materials to induce a charge-transfer complex. We also compared the gain coefficient of the photorefractive samples with the change of the concentration of the plasticizer, determined by two-beam coupling technique.

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Liu, Qingkun, Paul J. Ackerman, Tom C. Lubensky i Ivan I. Smalyukh. "Biaxial ferromagnetic liquid crystal colloids". Proceedings of the National Academy of Sciences 113, nr 38 (6.09.2016): 10479–84. http://dx.doi.org/10.1073/pnas.1601235113.

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The design and practical realization of composite materials that combine fluidity and different forms of ordering at the mesoscopic scale are among the grand fundamental science challenges. These composites also hold a great potential for technological applications, ranging from information displays to metamaterials. Here we introduce a fluid with coexisting polar and biaxial ordering of organic molecular and magnetic colloidal building blocks exhibiting the lowest symmetry orientational order. Guided by interactions at different length scales, rod-like organic molecules of this fluid spontaneously orient along a direction dubbed “director,” whereas magnetic colloidal nanoplates order with their dipole moments parallel to each other but pointing at an angle to the director, yielding macroscopic magnetization at no external fields. Facile magnetic switching of such fluids is consistent with predictions of a model based on competing actions of elastic and magnetic torques, enabling previously inaccessible control of light.

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