Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
Ab initio and density functional theory study of the electronic structure of rhenium complexes with noninnocent dioxolene ligands : Localized vs delocalized valence states. / Dmitriev, Alexey A.; Gritsan, Nina P.
в: International Journal of Quantum Chemistry, Том 119, № 23, 26018, 05.12.2019.Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
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TY - JOUR
T1 - Ab initio and density functional theory study of the electronic structure of rhenium complexes with noninnocent dioxolene ligands
T2 - Localized vs delocalized valence states
AU - Dmitriev, Alexey A.
AU - Gritsan, Nina P.
N1 - Publisher Copyright: © 2019 Wiley Periodicals, Inc.
PY - 2019/12/5
Y1 - 2019/12/5
N2 - The dioxolene type ligands (Diox) derived from ortho-quinones are the most widely studied redox noninnocent ligands existing in the dianionic (Cat), anion radical (SQ) or neutral (Q) forms although a highly delocalized electronic structure is also possible. For [ReO(Diox)2PPh3]− (2) and [ReCl3(Diox)PPh3] (3) complexes, the ReV-Cat2 and ReIV-SQ localized valence states were proposed on the basis of their XRD structures. To understand in detail the electronic structure of these complexes, we performed a series of the all-electron calculations at the DKH2-CASSCF/CASPT2 and DKH2-CASSCF/NEVPT2 levels taking into account scalar relativistic and spin-orbit effects. All calculations predicted that 2 has a singlet ground state with a predominant contribution of a single electronic configuration with doubly occupied molecular orbitals being pure o-quinone LUMOs of both Diox ligands that corresponds to the ReV-Cat2 valence state. Complex 3 has a triplet ground state with four electronic configurations contributing mainly into its wavefunction and differing by the occupation of bonding and antibonding combinations of the o-quinone LUMO and rhenium d-AO with nearly equal contributions. This leads to the empirical “metrical oxidation state” of dioxolene ligand being −1 that is usually referred to the ReIV-SQ oxidation state. However, in fact, the negative charge on the Diox ligand is mainly provided by a pair of electrons on the bonding MO. The standard DFT calculations entirely fail to correctly predict the ground state multiplicity for 3.
AB - The dioxolene type ligands (Diox) derived from ortho-quinones are the most widely studied redox noninnocent ligands existing in the dianionic (Cat), anion radical (SQ) or neutral (Q) forms although a highly delocalized electronic structure is also possible. For [ReO(Diox)2PPh3]− (2) and [ReCl3(Diox)PPh3] (3) complexes, the ReV-Cat2 and ReIV-SQ localized valence states were proposed on the basis of their XRD structures. To understand in detail the electronic structure of these complexes, we performed a series of the all-electron calculations at the DKH2-CASSCF/CASPT2 and DKH2-CASSCF/NEVPT2 levels taking into account scalar relativistic and spin-orbit effects. All calculations predicted that 2 has a singlet ground state with a predominant contribution of a single electronic configuration with doubly occupied molecular orbitals being pure o-quinone LUMOs of both Diox ligands that corresponds to the ReV-Cat2 valence state. Complex 3 has a triplet ground state with four electronic configurations contributing mainly into its wavefunction and differing by the occupation of bonding and antibonding combinations of the o-quinone LUMO and rhenium d-AO with nearly equal contributions. This leads to the empirical “metrical oxidation state” of dioxolene ligand being −1 that is usually referred to the ReIV-SQ oxidation state. However, in fact, the negative charge on the Diox ligand is mainly provided by a pair of electrons on the bonding MO. The standard DFT calculations entirely fail to correctly predict the ground state multiplicity for 3.
KW - DFT and CASSCF
KW - dioxolene ligands
KW - electronic structure
KW - metrical oxidation state
KW - rhenium complexes
KW - CATECHOLATE
KW - TRANSITION-METAL-COMPLEXES
KW - APPROXIMATION
KW - SEMIQUINONE
KW - CRYSTAL-STRUCTURE
KW - CORRELATION-ENERGY
KW - IMPLEMENTATION
KW - 2ND-ORDER PERTURBATION-THEORY
KW - BASIS-SETS
KW - TAUTOMERISM
UR - http://www.scopus.com/inward/record.url?scp=85069668127&partnerID=8YFLogxK
U2 - 10.1002/qua.26018
DO - 10.1002/qua.26018
M3 - Article
AN - SCOPUS:85069668127
VL - 119
JO - International Journal of Quantum Chemistry
JF - International Journal of Quantum Chemistry
SN - 0020-7608
IS - 23
M1 - 26018
ER -
ID: 21047339