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61.
The interaction between the radical anions C60
·− and divalent d- and f-metal (Co, Fe, Ni, Mn, Eu, Cd) cations in DMF and acetonitrile-benzonitrile (AN-BN) mixture was studied.
Black solid polycrystalline salts (C60
·−)2{(M2+)(DMF)
x
} (x = 2.4–4, 1–6) containing the radical anions C60
·− and metal(ii) cations solvated by DMF were prepared for the first time and their optical and magnetic properties were studied. The salts
containing Co2+, Fe2+, and Ni2+ are characterized by antiferromagnetic interactions between the radical anions C60
·−, which result in unusually large broadening of the EPR signal of C60
·− upon lowering the temperature (from 5.55–12.6 mT at room temperature to 35–40 mT at 6 K for Co2+ and Ni2+). The salts containing Mn2+ and Eu2+ form diamagnetic dimers (C60
−)2, which causes a jumpwise decrease in the magnetic moment of the complexes and disappearance of the EPR signal of C60
·− in the temperature range 210–130 K. A feature of salt 6 is magnetic isolation of the radical anions C60
·− due to the presence of diamagnetic cation Cd2+. The salts prepared are unstable in air and decompose in o-dichlorobenzene or AN. Reactions of C60
·− with metal(ii) cations in AN-BN mixture result in decomposition products of the salts that contain neutral fullerene dimers and metals
solvated by BN.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1909–1919, September, 2008. 相似文献
62.
A series of ionic multicomponent complexes comprising C60 and C70 anions and coordinating assemblies of methyldiazabicyclooctane cations with metal tetraphenylporphyrins, (MDABCO+)2.MIITPP.(C60(70)-)2.Sol. (C60, M = Zn (1); C60, M = Co (2); C60, M = Mn (3); C60, M = Fe (4); C70, M = Mn (5); and C70, M = Fe (6)) has been obtained. IR- and UV-vis-NIR spectra of 1-6 justified the formation of C60*- in 1-4 and single-bonded (C70-)2 dimers in 5 and 6. Co and Mn atoms are six-coordinated in the (MDABCO+)2.MIITPP units with relatively long M-N bonds of 2.475(2), 2.553(2), and 2.511(3) A for 2, 3, and 5, respectively. Isostructural complexes 2 and 3 contain C60*- zigzag chains separated by the (MDABCO+)2.MIITPP units, whereas in 5 the layers formed by the (C70-)2 dimers alternate with those composed of the (MDABCO+)2.MnIITPP units and noncoordinating MDABCO+ cations. Negative Weiss constants of -13 (1), -2 (3), and -2 (4) K indicate the antiferromagnetic interaction of spins, which decreases the magnetic moment of the complexes below 70-120 K. The EPR signals of 1 and 4 attributed to C60*- are split into two components at the same temperatures, which broaden and shift to higher and lower magnetic fields with the temperature decrease. Complexes 2 and 3 show single EPR signals with g-factors equal to 2.1082 and approximately 2.4 at 293 K, respectively. These values are mean between those characteristic of MIITPP and C60*-, and, consequently, the signals appear due to exchange coupling between these paramagnetic species. The antiferromagnetic ordering of C60*- spins below 70-100 K shifts g-factor values closer to those characteristic of individual MIITPP (g = 2.1907 (2) and approximately 4.9 (3) at 4 K). In contrast to 1-4, complex 5 shows paramagnetic behavior with Weiss constant close to 0. 相似文献
63.
Synthesis,Structures, and Properties of Crystalline Salts with Radical Anions of Metal‐Containing and Metal‐Free Phthalocyanines
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Dr. Dmitri V. Konarev Dr. Alexey V. Kuzmin Dr. Maxim A. Faraonov Dr. Manabu Ishikawa Dr. Salavat S. Khasanov Dr. Yoshiaki Nakano Dr. Akihiro Otsuka Prof. Hideki Yamochi Prof. Dr. Gunzi Saito Prof. Rimma N. Lyubovskaya 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(3):1014-1028
Radical anion salts of metal‐containing and metal‐free phthalocyanines [MPc(3?)].?, where M=CuII, NiII, H2, SnII, PbII, TiIVO, and VIVO ( 1 – 10 ) with tetraalkylammonium cations have been obtained as single crystals by phthalocyanine reduction with sodium fluorenone ketyl. Their formation is accompanied by the Pc ligand reduction and affects the molecular structure of metal phthalocyanine radical anions as well as their optical and magnetic properties. Radical anions are characterized by the alternation of short and long C?Nimine bonds in the Pc ligand owing to the disruption of its aromaticity. Salts 1 – 10 show new bands at 833–1041 nm in the NIR range, whereas the Q‐ and Soret bands are blue‐shifted by 0.13–0.25 eV (38‐92 nm) and 0.04–0.07 eV (4–13 nm), respectively. Radical anions with NiII, SnII, PbII, and TiIVO have S=1/2 spin state, whereas [CuIIPc(3?)].? and [VIVOPc(3?)].? containing paramagnetic CuII and VIVO have two S=1/2 spins per radical anion. Central metal atoms strongly affect EPR spectra of phthalocyanine radical anions. Instead of narrow EPR signals characteristic of metal‐free phthalocyanine radical anions [H2Pc(3?)].? (linewidth of 0.08–0.24 mT), broad EPR signals are manifested (linewidth of 2–70 mT) with g‐factors and linewidths that are strongly temperature‐dependent. Salt 11 containing the [NaIPc(2?)]? anions as well as previously studied [FeIPc(2?)]? and [CoIPc(2?)]? anions that are formed without reduction of the Pc ligand do not show changes in molecular structure or optical and magnetic properties characteristic of [MPc(3?)].? in 1 – 10 . 相似文献
64.
R. M. Vlasova B. V. Petrov V. N. Semkin E. I. Zhilyaeva S. A. Torunova R. N. Lyubovskaya 《Physics of the Solid State》2013,55(9):1913-1919
The polarized reflectance spectra of microcrystals of the new organic superconductor (EDT-TTF)4[Hg3I8]1 ? x (T c = 8.1 K for x = 0.027; T c = 7 K at 0.3 kbar for x = 0.019) have been investigated in the spectral region of 700–6000 cm?1 (0.087–0.740 eV) at temperatures ranging from 10 to 300 K. A quantitative analysis of the spectra has been performed in the framework of the phenomenological Drude and Drude-Lorentz dispersion models, as well as in the framework of the theoretical “phase phonon” model that takes into account the interaction of free electrons with intramolecular vibrations. The effective mass of charge carriers m*, the width of the initial metallic π-electron band W, and the integral t of the electron transfer between the molecular π-orbitals of neighboring molecules have been determined. In the low-frequency range (700–1600 cm?1), the vibrational structure associated with intramolecular vibrations of the EDT-TTF molecule has been revealed. It has been shown that the most intense feature (ω = 1330 cm?1) of this structure is caused by the interaction of “quasi-free” electrons with intramolecular vibrations. 相似文献
65.
Konarev DV Kuźmin AV Simonov SV Khasanov SS Yudanova EI Lyubovskaya RN 《Dalton transactions (Cambridge, England : 2003)》2011,40(17):4453-4458
New ionic complex {Co(+)(dppe)(2)}·(C(60)˙(-))·(C(6)H(4)Cl(2))(2) (1) was obtained by the reduction of a Co(dppe)Br(2) and C(60) mixture by TDAE in o-dichlorobenzene followed by precipitation of crystals by hexane. Optical and EPR spectra of 1 indicated the formation of C(60)˙(-) radical anions and diamagnetic Co(+)(dppe)(2) cations. The structure of 1 solved at 100(2) K involves chains of C(60)˙(-) arranged along the lattice a-axis with a center-to-center distance of 10.271 ?. The chains are separated by bulky Co(+)(dppe)(2) cations and solvent molecules. All components of 1 are well ordered allowing the distortion of the C(60)˙(-) radical anion to be analyzed. An elongation of the C(60)˙(-) sphere by 0.0254(2) was found. It is essentially smaller than those in the salts (Cp*(2)Ni(+))·(C(60)˙(-))·CS(2) and (PPN(+))(2)·(C(60)(2-)) with greater distortion of the fullerene cage. The calculation of the electronic structure of fullerene by the extended Hückel method showed slight splitting of the C(60) LUMO, due to the distortion, by three levels. Two levels are located 180 and 710 cm(-1) higher than the ground level. The averaged 6-6 and 5-6 bonds in C(60)˙(-) with lengths of 1.397(2) and 1.449(2) ? are close to those determined for the C(60)(2-) dianions in (PPN(+))(2)·(C(60)(2-)), but are slightly longer and shorter, respectively, than the length of these bonds in neutral C(60). 相似文献
66.
67.
68.
D.V. KonarevA.Yu. Kovalevsky A.L. LitvinovN.V. Drichko B.P. TarasovP. Coppens R.N. Lyubovskaya 《Journal of solid state chemistry》2002,168(2):474-485
New molecular complexes of fullerenes C60 and C70 with leuco crystal violet (LCV, 1-3); leucomalachite green (LMG, 4-6); crystal violet lactone (CVL, 7); N,N,N′,N′-tetrabenzyl-p-phenylenediamine (TBPDA, 8, and 9); N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPDA, 10, and 11); triphenylamine (TPA, 12, and 13); and substituted phenotellurazines (EPTA and TMPTA, 14, and 15) have been synthesized. Crystal structures have been solved for C60 complexes with LMG (5, 6) TBPDA (8), TMPDA (10), and TPA (12). The C60 molecules form closely packed double layers in 5 and 6, hexagonal layers in 10 and quasi-three-dimensional layers in 8 and 12. The substitution of disordered solvent molecules in the complexes with LMG (4, 5) by naphthalene ones results in the ordering of the C60 molecules. According to IR-, UV-visible-NIR and ESR-spectroscopy the complexes have a neutral ground state. The spectra of 1-8, and 10 show intense charge transfer bands in the visible and NIR-range. On photoexcitation by white light (light-induced ESR (LESR) spectroscopy), 1 and 10 were shown to have an excited ionic state. The LESR signals were generated at light energies <2.25 eV indicating that the excited states in the complexes are realized mainly by direct charge transfer from donor to the C60 molecule. 相似文献
69.
D. V. Konarev V. N. Semkin A. Graja R. N. Lyubovskaya 《Journal of Molecular Structure》1998,450(1-3):11-22
Charge transfer complexes of fullerene C60 with planar donors of tetrathiafulvalene, dithiadiazafulvalene and pyranylidene family were investigated by IR- and UV-VIS-NIR spectroscopy. The analysis of IR and X-ray data shows that the charge transfer complexes of fullerene with the planar donors are involved in polarization interactions of van der Waals type. Charge transfer is very weak in these compounds and is hindered by unfavourable steric factors. As a result, the CT rate does not correlate with the ionization potential of the donor; the charge transfer absorption bands are very weak too. 相似文献
70.
V. V. Gritsenko O. A. D'yachenko D. V. Konarev R. N. Lyubovskaya 《Russian Chemical Bulletin》1990,49(1):102-105
A new C70-based molecular complex 4BNDY·3C70·4C6H6 (1) (BNDY is binaphtho[1,8-d.e]-1,3-dithiin-2-ylidene) was prepared, and its full X-ray diffraction study at room temperature was performed. The C70 molecules in crystal 1 are ordered in different ways, and their ordering depends on van der Waals interactions between them
and nonplanar BNDY molecules in the boat conformation. The neighboring BNDY molecules in the structure are bound to each other
by π-π interactions.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 99–102, January, 2000. 相似文献