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61.
Dmitri V. Konarev Alexey V. Kuzmin Salavat S. Khasanov Rimma N. Lyubovskaya 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(5):449-451
The title complex salt, (C16H36N)[MnBr(C32H16N8)] or (TBA)[MnIIBr(Pc)] (TBA is tetrabutylammonium and Pc is phthalocyaninate), has been obtained as single crystals by the diffusion technique and its crystal structure was determined using X‐ray diffraction. The high‐spin (S = ) [MnIIBr(Pc)]− macrocycle has a concave conformation, with an average equatorial Mn—N(Pc) bond length of 2.1187 (19) Å, an axial Mn—Br bond length of 2.5493 (7) Å and with the MnII cation displaced out of the 24‐atom Pc plane by 0.894 (2) Å. The geometry of the MnIIN4 fragment in [MnIIBr(Pc)]− is similar to that of the high‐spin (S = ) manganese(II) tetraphenylporphyrin (TPP) in [MnII(1‐MeIm)(TPP)] (1‐MeIm is 1‐methylimidazole). 相似文献
62.
Russian Journal of Electrochemistry - Effect of the naphthalene 2-nitro-4,8-disulfonic acid preparative reduction conditions on the naphthalene 2-amino-4,8-disulfonic acid yield and current... 相似文献
63.
Dr. Maxim V. Mikhailenko Dr. Salavat S. Khasanov Prof. Alexader F. Shestakov Dr. Aleksey V. Kuzmin Akihiro Otsuka Hideki Yamochi Hiroshi Kitagawa Dr. Dmitri V. Konarev 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(10):e202104165
Hexaazatrianthracene (HATA) and hexaazatriphenylenehexacarbonitrile {HAT(CN)6} are reduced by metallic iron in the presence of crystal violet (CV+)(Cl−). Anionic ligands are produced, which simultaneously coordinate three FeIICl2 to form (CV+)2{HATA ⋅ (FeIICl2)3}2− ⋅ 3 C6H4Cl2 ( 1 ) and (CV+)3{HAT(CN)6. (FeIICl2)3}3− ⋅ 0.5CVCl ⋅ 2.5 C6H4Cl2 ( 2 ). High-spin (S=2) FeII atoms in both structures are arranged in equilateral triangles at a distance of 7 Å. An antiferromagnetic exchange is observed between FeII in {HATA ⋅ (FeIICl2)3}2− ( 1 ) with a Weiss temperature (Θ) of −80 K, the PHI estimated exchange interaction (J) is −4.7 cm−1. The {HAT(CN)6 ⋅ (FeIICl2)3}3− assembly is obtained in 2 . The formation of HAT(CN)6.3− is supported by the appearance of an intense EPR signal with g=2.0037. The magnetic behavior of 2 is described by a strong antiferromagnetic coupling between the FeII and HAT(CN)6.3− spins with J1=−164 cm−1 (−2 J formalism) and by a weaker antiferromagnetic coupling between the FeII spins with J2=−15.4 cm−1. The stronger coupling results in the spins of the three FeIICl2 units to be aligned parallel to each other in the assembly. As a result, an increase of the χMT values is observed with the decrease of temperature from 9.82 at 300 K up to 15.06 emu ⋅ K/mol at 6 K, and the Weiss temperature is also positive being at +23 K. Thus, a change in the charge and spin state of the HAT-type ligand to ⋅3− results in ferromagnetic alignment of the FeII spins, yielding a high-spin (S=11/2) system. DFT calculations showed that, due to the high symmetry and nearly degenerated LUMO of both HATA and HAT(CN)6, their complexes with FeIICl2 have a variety of closely lying excited high-spin states with multiplicity up to S=15/2. 相似文献
64.
65.
Russian Journal of Electrochemistry - Electrochemical behavior of naphthalene 1-nitro-6-sulfonic acid was studied by polarography, voltammetry on glassy carbon electrodes, and electrolysis at... 相似文献
66.
Marchenkova M. A. Konarev P. V. Boikova A. S. Ilina K. B. Pisarevsky Yu. V. Kovalchuk M. V. 《Crystallography Reports》2021,66(5):751-757
Crystallography Reports - The influence of the precipitant type (LiCl, NaCl, KCl, NiCl2, and CuCl2) on the formation of oligomers (dimers and octamers) in lysozyme crystallization solutions at two... 相似文献
67.
Crystallography Reports - The stabilities of reconstructing the solution to the problem of determining the volume particle size distributions are compared by the example of small-angle scattering... 相似文献
68.
D. V. Konarev N. V. Drichko R. N. Lyubovskaya Yu. M. Shul''ga A. L. Litvinov V. N. Semkin Yu. A. Dubitsky A. Zaopo 《Journal of Molecular Structure》2000,526(1-3):25-29
A molecular complex of fullerene C60 with triptycene, TPC·C60 is obtained. The complex has a three-dimensional packing of C60 molecules. According to the IR spectra, the freezing of free rotation of C60 molecules in the complex is maintained up to 360 K. The XP-spectra of TPC·C60 show the suppression of π–π* transitions of TPC phenylene rings. The separation of C60 molecules by TPC ones in TPC·C60 results in low intensity of the C60 transitions in the 420–500 nm range in an optical spectrum. This absorption is assumed as that attributed to intermolecular transitions between adjacent C60 molecules. 相似文献
69.
Shtykova EV Malyutin A Dyke J Stein B Konarev PV Dragnea B Svergun DI Bronstein LM 《The journal of physical chemistry. C, Nanomaterials and interfaces》2010,114(50):21908-21913
Aqueous solutions of iron oxide nanoparticles (NPs) stabilized by poly(maleic acid-alt-1-octadecene) (PMAcOD) modified with the 5,000 Da poly(ethylene glycol) (PEG) or the short ethylene glycol (EG) tails were analyzed by small-angle X-ray scattering (SAXS). Advanced SAXS data analysis methods were employed to systematically characterize the structure and interactions between the NPs. Depending on the type of the grafted tail and the grafting density all NPs can be separated into three groups. All the samples contain mixtures of individual nanoparticles, their dynamic clusters and aggregates, and the fractions of these species are different in the different groups. The first group consists of NPs coated with PMAcOD modified with the long PEG tails with the maximal grafting density, and the content of dynamic clusters and aggregates in the samples of this group does not exceed 4%. The samples from the second group with less dense coatings demonstrate a larger amount (5-7%) of the aggregates and dynamic clusters. The samples from the third group consisting of the NPs protected by EG modified PMAcOD contain mostly individual NPs and some amount of dumbbell dimers without noticeable aggregation. Importantly, the solution behavior of the NPs is independent on the iron oxide core size. Our results therefore provide means of predicting stabilization and avoiding aggregation of NPs based on the type of a protective shell. 相似文献
70.
Richard DV. Espiritu Alberto V. AmorsoloJr. 《Journal of Thermal Analysis and Calorimetry》2012,107(2):483-487
Cu–Zn–Sn shape memory alloy strips with composition range of 13.70–46.30 mass% Sn were fabricated by electrodepositing Sn
on a shim brass surface and then subsequently annealed at a constant temperature of 400 °C for 120 min under flowing nitrogen.
Subjecting the Sn-plated strips to differential scanning calorimetry (DSC) analysis revealed that the austenitic start (A
s) temperature was essentially constant at 225 °C while the martensite start (M
s) temperature was consistently within the 221.5–222 °C interval. Austenite to martensite phase transformation showed two distinct
peaks on the DSC thermogram which can be attributed to the non-homogeneity of the bulk Cu–Zn–Sn ternary alloy. The latent
heats of cooling and heating were found to increase with the mass% Sn plated on the shim brass. Effect of annealing temperature
was also investigated wherein strips with an essentially constant composition of 26 mass% Sn were annealed at a temperature
range of 350–420 °C for 120 min under flowing nitrogen. Varying the annealing temperature has no significant effect on the
transformation temperatures of the ternary alloy. 相似文献