Broken symmetry density functional study of biomimetic models for Purple Acid Phosphatases of the type Fe(III)-M(II) (M = Fe, Cu, Ni, Co and Mn)

被引：9

作者：

Ferreira, Dalva E. C. ^{[2
]}

De Almeida, Wagner B. ^{[1
]}

Neves, Ademir ^{[3
]}

Rocha, Willian R. ^{[1
]}

机构：

[1] Univ Fed Minas Gerais, Dept Quim ICEX, LQC MM Lab Quim Computac & Modelagem Mol, BR-31270901 Belo Horizonte, MG, Brazil

[2] Univ Fed Vales Jequitinhonha & Mucuri, Dept Quim, BR-39100000 Diamantina, MG, Brazil

[3] Univ Fed Santa Catarina, Dept Quim, LABINC Lab Quim Bioinorgan & Cristalog, BR-88040900 Florianopolis, SC, Brazil

来源：

COMPUTATIONAL AND THEORETICAL CHEMISTRY | 2012年 / 979卷

关键词：

Mixed valence complexes; Biomimetic compounds; Magnetic coupling constant; Broken symmetry; Density Functional Theory; EXCHANGE COUPLING-CONSTANTS; TRANSITION-METAL-COMPLEXES; BASIS-SETS; MAGNETOSTRUCTURAL CORRELATIONS; MAGNETIC-PROPERTIES; HARTREE-FOCK; RESONANCE; VALENCE; LIGAND; APPROXIMATION;

D O I：

10.1016/j.comptc.2011.10.020

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Density Functional Theory (OFT) calculations using the hybrid meta-GGA TPSSh functional, were carried out for mixed valence compounds Fe(III)-M(II)(M = Fe, Cu, Ni, Co and Mn) which are structural and functional biomimetic models for Purple Acid Phosphatases. The broken symmetry (BS) formalism was used to compute the magnetic coupling constant which shows that all complexes exhibit weak antiferromagnetic coupling. The effect of the geometry on the accuracy of the BS calculations is evaluated and it is shown that the TPSSh functional provides accurate results with errors in the range of 10-19%, as long as the geometry around the transition metal ions is well described. All complexes show one magnetic exchange sigma/pi pathway involving the in-plane p-orbitals of the phenoxo bridge and the metal d-orbitals. Additionally, a correlation between the computed coupling constant and the M-II-O(bridge) bond distance is found, in agreement with the experimental findings. (C) 2011 Elsevier B.V. All rights reserved.

引用

页码：89 / 95

页数：7

共 56 条

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