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Theoretical Study of Vanadate Complexes with MO4 Tetraoxo Anions in the Inner Sphere of the Mixed-Valence V20O46 Clusterстатья
- Авторы: Charkin O.P., Klimenko N.M.
- Журнал: Russian Journal of Inorganic Chemistry
- Том: 65
- Номер: 7
- Год издания: 2020
- Издательство: Maik Nauka/Interperiodica Publishing
- Местоположение издательства: Russian Federation
- Первая страница: 1032
- Последняя страница: 1039
- DOI: 10.1134/s0036023620060029
- Аннотация: Calculations of high-spin isomers of MO4V20O46(n−) anions (S = 9) with MO4 tetraoxo anions located in the inner and outer spheres of the mixed-valence V20O46 cage have been performed by the density functional theory method. It has been shown that for all systems the endohedral isomers are considerably more favorable than the exohedral isomers. For the complexes with transition metal atoms M (M = Ti, V, Cr), the centered ortho isomer MO4@V20O46(n−) is clearly more preferable. For the complexes with main-group metal atoms (M = Si, Ge, P, As, S, Se), the meta isomer MO3@V20O47(n−) has been localized in addition to ortho-MO4@V20On−46 . The meta isomer has a pyramidal МО3 anion and the fourth oxygen atom bound to a trivalent vanadium atom of the cage through an inner О=VIII bond. For complexes with SO4(2−) and SeO4(2−) dianions, both ortho and meta structures do not correspond to stationary points of the potential energy surface: upon optimization, they convert without a barrier to the MO2@V20O48(2−) isomer with two М−О−V(III) bridges and two inner О=V(III) The character of geometric distortions, normal mode shifts, and electron and spin density redistribution between the inserted MO4 guest and the cage as compared with isolated MOn−4 and V20O46 systems has been considered. The results are compared with previous calculations of MO4@V20O50(n−) complexes with the same anions into the valence-saturated V20O50 cluster. The stability and structure of the “nested” V4O6@V20O50 (S = 9) cluster with the more complex tetrahedral guest V4O6 inside the V20O50 cage are predicted.
- Добавил в систему: Чаркин Олег Петрович