QUANTUM CHEMICAL SIMULATION OF trans- AND cis-ISOMERS OF bis-CHELATE AZOMETHINE COMPLEXES OF Ni(II), Pd(II), AND Pt(II) WITH THE MN2Y2 (Y = O, S, Se) COORDINATION CORE
N. N. Kharabayev1, A. G. Starikov1,2, V. I. Minkin1,2
1Southern Federal University, Rostov-on-Don, Russia
2Southern Scientific Center, Rostov-on-Don, Russia
Keywords: квантовая химия, молекулярная структура, хелатные комплексы металлов, ароматические азометины, quantum chemistry, molecular structure, metal chelate complexes, aromatic azomethines
Abstract
Within density functional theory the experimentally observed stereoeffects of the ligand environment in low-spin bis-chelates of Ni(II), Pd(II), and Pt(II) with aromatic azomethines is modeled. It is shown that complexes with the MN2O2 coordination core are characterized by the trans -configuration and in complexes with MN2S2 or MN2Se2 cores the stabilization of the cis -configuration occurs. The relationship is found between the composition of metal cycles and their conformation (an inflection along the donor atom line), the degree of steric hindrances in the cis -configuration due to the interligand interaction of R substituents at azomethine nitrogen atoms and the relative stability of cis - and trans -isomers of the complex.
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