A Dichromium(II) BiS(η8-pentalene) double-sandwich complex with a spin equilibrium:: Synthetic, structural, magnetic, and theoretical studies

被引：29

作者：

Balazs, Gabor ^{[2
]}

Cloke, F. Geoffrey N. ^{[1
]}

Gagliardi, Laura ^{[4
]}

Green, Jennifer C. ^{[2
]}

Harrison, Andrew ^{[3
]}

Hitchcock, Peter B. ^{[1
]}

Shahi, Abdul Reharnan Moughal ^{[4
]}

Summerscales, Owen T. ^{[1
]}

机构：

[1] Univ Sussex, Sch Life Sci, Dept Chem, Brighton BN1 9QJ, E Sussex, England

[2] Univ Oxford, Inorgan Chem Lab, Dept Chem, Oxford OX1 3QR, England

[3] Univ Edinburgh, Sch Chem, Edinburgh EH9 3JJ, Midlothian, Scotland

[4] Univ Geneva, Dept Phys Chem, CH-1211 Geneva, Switzerland

来源：

ORGANOMETALLICS | 2008年 / 27卷 / 09期

关键词：

D O I：

10.1021/om701153t

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The new bis(pentalene) complex Cr-2(eta(5):eta(5)-C8H4 (1,4-Si1Pr3))(2) has been synthesized and characterized; it is found to exhibit paramagnetism at room temperature, and solid-state magnetic studies show that the dimer is best modeled as containing a pair of antiferromagnetically interacting S = 1/2 centers with the separation between the singlet ground state and triplet excited state being 2.23 kJ mol(-1). Structural data show a Cr-Cr distance of 2.2514(15) angstrom, consistent with a strong metal-metal interaction. The bonding has been further investigated by density functional, hybrid, and CASPT2 methods. The metal-metal interaction is best described by a double bond with each metal having an 18-electron count. Theory predicts the singlet and triplet states to lie close in energy but puts the triplet state at a slightly lower energy than the singlet. The energy difference predicted by CASPT2 is closest to the experimental value.

引用

页码：2013 / 2020

页数：8