Structural and spectroscopic studies of valence-delocalized diiron(III) complexes supported by carboxylate-only bridging ligands

被引：29

作者：

Lee, D

DuBois, JL

Pierce, B

Hedman, B

Hodgson, KO

Hendrich, MP

Lippard, SJ ^{[1
]}

机构：

[1] Stanford Univ, Dept Chem, Stanford, CA 94305 USA

[2] MIT, Dept Chem, Cambridge, MA 02139 USA

[3] Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA

[4] Carnegie Mellon Univ, Dept Chem, Pittsburgh, PA 15213 USA

来源：

INORGANIC CHEMISTRY | 2002年 / 41卷 / 12期

关键词：

D O I：

10.1021/ic011050n

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The synthesis, molecular structures, and spectroscopic properties of a series of valence-delocalized diiron(II,III) complexes are described. One-electron oxidation of diiron(II) tetracarboxylate complexes afforded the compounds [Fe-2(mu-O2CArTol)(4)L-2]X, where L = 4-(BuC5H4N)-Bu-t (1b), C5H5N (2b), and THF (3b); X = PF6- (1b and 3b) and OTf- (2b). In 1b-3b, four mu-1,3 carboxylate ligands span relatively short Fe...Fe distances of 2.6633(11)-2.713(3) Angstrom. Intense (epsilon = 2700-3200 M-1 cm(-1)) intervalence charge transfer bands were observed at 620-670 nm. EPR spectroscopy confirmed the S = (9)/(2) ground spin state of 1b-3b, the valence-delocalized nature of which was probed by X-ray absorption spectroscopy. The electron delocalization between paramagnetic metal centers is described by double exchange, which, for the first time, is observed in diiron clusters having no single-atom bridging ligand(s).

引用

页码：3172 / 3182

页数：11

共 57 条

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