학술논문
Spin-crossover in complexes of iron(II) carboranes with tris(pyrazol-1-yl)methane.
Document Type
Article
Source
Subject
*IRON compounds
*CARBORANES
*METHANE
*CHEMICAL synthesis
*COORDINATION compounds
*MAGNETOCHEMISTRY
*TRANSITION temperature
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Language
ISSN
0022-4766
Abstract
Synthesis procedures for coordination compounds of iron(II) 1,5,6,10-tetra(R)-7,8-dicarba- nido-undecaborates(-1) (carboranes) with tris(pyrazol-1-yl)methane (HC(pz)) of the composition [Fe{HC(pz)}]A· nHO (A = (7,8-CBH) ( I), (1,5,6,10-Br-7,8-CBH) ( II), (1,5,6,10-I-7,8-CBH) ( III), n = 0-2) are developed. The compounds are studied by static magnetic susceptibility in the temperature range of 160-500 K, electron (diffuse reflectance spectra), IR, and Mössbauer spectroscopy methods. It is shown that the complexes have high-temperature spin-crossover A ⇔ T. Transition temperatures ( T) for I-III are 370 K, 380 K, and 400 K respectively. Spin-crossover is accompanied by thermochromism (color change: pink ⇔ white). [ABSTRACT FROM AUTHOR]