| Autor: |
Polestshuk, Pavel M., Dem'yanov, Piotr I., Ryabinkin, Ilya G. |
| Předmět: |
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| Zdroj: |
Journal of Chemical Physics; 8/7/2008, Vol. 129 Issue 5, p054307, 13p, 2 Diagrams, 8 Charts, 1 Graph |
| Abstrakt: |
Multireference [complete active space self-consistent field (CASSCF) and multiconfigurational quasidegenerate perturbation theory (MCQDPT)] and single-reference ab initio (Mo\ller–Plesset second order perturbation theory (MP2) and coupled clusters with singles, doubles and noniterative triples [CCSD(T)]) and density functional theory (PBE and B3LYP) electronic structure calculations of V(C6H6)+ half-sandwich in the states of different multiplicities are described and compared. Detailed analyses of the geometries and electronic structures of the all found states are given; adiabatic and diabatic dissociation energies are estimated. The lowest electronic state of V(C6H6)+ half-sandwich was found to be the quintet 5B2 state with a slightly deformed upside-down-boat-shaped benzene ring and d4 configuration of V atom, followed by a triplet 3A2 state lying about 4 kcal/mol above. The lowest singlet state 1A1(d4) lies much (∼28 kcal/mol) higher. MCQDPT calculated adiabatic dissociation energy (53.6 kcal/mol) for the lowest 5B2(d4) state agrees well with the current 56.4 (54.4) kcal/mol experimental estimate, giving a preference to the lower one. Compared to MCQDPT, B3LYP hybrid exchange-correlation functional provides the best results, while CCSD(T) performs usually worse. Gradient-corrected PBE calculations tend to systematically overestimate metal-benzene binding in the row quintet≤triplet≤singlet. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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