А. Б. Захаров, В. В. Иванов
Харьковский национальный университет им. В.Н. Каразина vivanov@univer.kharkov.ua
Ключевые слова: поляризуемость, гиперполяризуемость, метод CCSD, метод FCI
Страницы: 667-673
В π-электронных расчетах поляризуемостей и гиперполяризуемостей сопряженных систем, в рамках теории связанных кластеров предлагается использовать орбитальный базис молекул этилена. Тестовые расчеты говорят о высокой точности метода в сравнении с методом полного конфигурационного взаимодействия.
Н. М. Витковская1, Е. Ю. Ларионова1, Н. В. Кэмпф1, В. Б. Кобычев1, Б. А. Трофимов2 1 Иркутский государственный университет 2 Учреждение Российской академии наук Иркутский институт химии им. А.Е. Фаворского СО РАН lari555@mail.ru, boris_trofimov@irioch.irk.ru
Ключевые слова: метанол, гидроксид щелочного металла, винилирование, механизмы реакций, квантово-химические расчеты
Страницы: 674-680
Выполнено сравнительное неэмпирическое квантово-химическое исследование взаимодействия метанола с гидроксидами калия и рубидия, находящимися в окружении молекул ДМСО. Рассмотрены профили реакций образования нуклеофильной частицы при непосредственном взаимодействии метанола с недиссоциированной молекулой гидроксида щелочного металла. Проведено сопоставление уровней описания реагирующей системы континуально-кластерными моделями различной сложности.
Н. М. Витковская1, Е. Ю. Ларионова1, Н. В. Кэмпф1, В. Б. Кобычев1, А. Д. Скитневская1, В. Б. Орел1, Б. А. Трофимов2 1 Иркутский государственный университет 2 Учреждение Российской академии наук Иркутский институт химии им. А.Е. Фаворского СО РАН lari555@mail.ru
Ключевые слова: метанол, метантиол, ацетоксим, гидроксид щелочного металла, винилирование, механизмы реакций, квантово-химические расчеты
Страницы: 681-685
Для газовой фазы, а также с явным включением в расчет молекулы диметилсульфоксида и учетом эффектов сольватации в рамках континуальной модели выполнено неэмпирическое квантово-химическое исследование профилей реакций образования нуклеофильных частиц при взаимодействии метанола, метантиола и ацетоксима с недиссоциированной молекулой гидроксида щелочного металла.
R. Islampour, M. Gharibi, A. Khavaninzadeh
Department of Chemistry Tarbiat Moallem University islampour@tmu.ac.ir
Ключевые слова: rare gas dimers, DVR method, vibration-rotation energy levels
Страницы: 686-695
The vibration-rotation energy level spacings of homo- and heteronuclear rare gas dimers are calculated for some more common analytical intermolecular potential energy functions in a unified way by employing the discrete variable representation (DVR) method.
X. Kuang1, X. Wang2, G. Liu2 1 College of Mathematics and Physics Chongqing University School of Science, Southwest University of Science and Technology 2 College of Mathematics and Physics Chongqing University xkdkxj@yahoo.com.cn
Ключевые слова: MRh12 cluster, geometrical structure, electronic and magnetic properties
Страницы: 696-703
In this paper, a first-principles study on the stability, electronic and magnetic properties of MRh12 (M = Rh, Fe, Co and Ni) clusters is performed. By optimizing the geometrical structure, we find that MRh12 clusters change from a perfect icosahedron to a distorted structure and have an obvious bond length contraction as compared with the corresponding bulk phase; FeRh12, CoRh12, and NiRh12 clusters are more energetically stable than the RhRh12 cluster. The effect of the impurity M on the density of states, valence band width, HOMO and LUMO for MRh12 clusters is not significant, but when the central Rh atom is substituted with M, the magnetic moment of MRh12 reduces dramatically. The Mulliken population analysis indicates that there are more charge transfers from other orbitals to Rh4d and M3d orbitals, and the spd hybrid effect in d orbitals of MRh12 clusters is stronger than that in the RhRh12 cluster. this situation means that the unpaired d electrons have more chance to be paired, and the magnetic moments of MRh12 clusters can be reduced reasonably.
R. Ghiasi1, A. Moghimi2 1 Department of Chemistry Basic Science Faculty East Tehran Branch Qiam Dasht Tehran Islamic Azad University 2 Department of Chemistry Pishva-Varamine Branch Varamine Islamic Azad University rezaghiasi1353@yahoo.com, rghyasi@qdiau.ac.ir
Ключевые слова: metals-π interaction energy, natural bond orbital (NBO), atoms in molecules methodology (AIM)
Страницы: 704-710
The nature of [HB≡CH]-, [H2B=CH2]-, and boratabenzene interactions with alkaline and alkaline earth metals are studied by ab initio calculations. The interaction energies are calculated at the B3LYP/6-311++G(d,p) level. The calculations suggest that the cation size and charge are two influential factors that affect the nature of the interaction. AIM and NBO analyses of the complexes indicate that the variation of densities and the extent of charge transfers upon complexation correlate well with the obtained interaction energies.
M. Altaf1, H. Stoeckli-evans1, G. Murtaza2, A.A. Isab3, S. Ahmad2, M.A. Shaheen4 1 Institute of Physics, University of Neuchâtel 2 Department of Chemistry, University of Engineering and Technology 3 Department of Chemistry, King Fahd University of Petroleum and Minerals 4 Department of Chemistry, University of Sargodha saeed_a786@hotmail.com
Ключевые слова: cadmium sulfate, N, N?-diethylthiourea, crystal structure
Страницы: 640-644
A cadmium(II) complex, tetrakis(N,N′-diethylthiourea)sulfatocadmium(II), [Cd(Detu)4SO4] (1) was prepared and its crystal structure was determined by x-ray crystallography. The crystal structure of the complex consists of an independent molecule with the central cadmium atom coordinated to four thione sulfur atoms of Detu and two oxygen atoms of the sulfate ligand. The Cd atom has a pseudo-octahedral coordination environment with the cis angles varying from 57.68 to 126.57°, while the trans angles fall in the range of 142 to 169°. The new complex was also characterized by IR and NMR spectroscopy and the spectroscopic data are discussed in terms of the nature of bonding.
A novel bimetallic 4f-3d metal-isonicotinic acid inorganic-organic hybrid complex [Tb0.5(C6NO2H5)3(H2O)2]2n·(H3O)4n(ZnCl5)n(ZnCl4)2n (1) is synthesized. It has a one-dimensional polycationic chain-like structure. Photoluminescent investigation reveals that it displays interesting emissions in the violet, blue, green, and yellow regions.
YA.-G. Hu1, X.-B. Chen1, H.-T. Gao1, M.-W. Ding2 1 Institute of Medicinal Chemistry, Hubei University of Medicine 2 Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Central China Normal University huyangg111@yahoo.com.cn
Ключевые слова: crystal structure, benzo[4, 5]furo[3, 2-d]pyrimidin-4(3H)-one, aza-Wittig reaction
Страницы: 649-652
The title compound (C20H18FN3O2, Mr = 351.37) is prepared and its crystal structure is determined by single crystal X-ray diffraction. The crystal is tetragonal, the P-42(1)c space group with a = 11.0922(6), b = 11.0922(6), c = 28.6271(15) Å, V = 3522.2(3) Å3, Z = 8, dx = = 1.325 g/cm3, F(000) = 1472, μ = 0.095 mm-1, MoKα radiation (λ = 0.71073), R = 0.0505, wR = 0.1090 for 2433 observed reflections with I > 2σ(I). The X-ray diffraction analysis reveals that all ring atoms in the benzo[4,5]furo[3,2-d]pyrimidinone moieties are almost coplanar.
A. Abbasi, S. Zamanian, S. Tarighi, A. Badiei
School of chemistry, College of Science, University of Tehran aabbasi@khayam.ut.ac.ir
Ключевые слова: benzothiophene, carboxamide, crystal structure, hydrogen bonding, CH-π interaction, π-π interaction
Страницы: 653-656
3-chloro-N-(8′-quinolyl)benzo[b]thiophene-2-carboxamide was synthesized from 3-chlorobenzo[b] thiophene -2-carboxyl chloride and 8-aminoquinoline in the presence of triethylamine. The single crystal X-ray structure determination confirmed the earlier proposed structure and also characterized by 1HNMR, and Mass spectroscopy. Crystallographic study reveals that the structure crystallizes in monoclinic system, a = 14.878(4), b = 8.4292(15), c = 25.461(7) Å, β = 112.022(18)°, Z = 8, V = 2960.20(12) Å3 with space group C2/c (No. 15). In the structure packing, three kinds of interactions are responsible for the stability of the structure. Infinite two-dimensional stair-like layered chains are formed by relatively strong intermolecular hydrogen bonds [C14-H14…O1]. These parallel chains are connected by several π-π and CH-π interactions, alternatively. There are two such parallel chains with 70.53°, which are in contact by van der Waals interactions.
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