Photochemical formations of super high-spin molecules consisting of carbenes and metal ions in frozen solutions

被引：17

作者：

Karasawa, S ^{[1
]}

Koga, N ^{[1
]}

机构：

[1] Kyushu Univ, Grad Sch Pharmaceut Sci, Fukuoka 8128582, Japan

来源：

POLYHEDRON | 2001年 / 20卷 / 11-14期

关键词：

magnetic property; matrix; heterospin system; photolysis; carbene; Cu(hfac)(2); hysteresis;

D O I：

10.1016/S0277-5387(01)00624-6

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

Diazo-pyridine compounds 2-4 were prepared as new types of spin sources/magnetic couplers. The molecular structures of 2-4 were determined by X-ray analyses. Photolysis of 2-4 in MTHF frozen solution at cryogenic temperature was followed by EPR spectra and magnetic susceptibility measurements on a SQUID magnetometer/susceptometer. The EPR spectra and the field dependence of magnetization (M) after photolysis of 2, 3, and 4 suggested that their photoproducts are quintet, septet, and undecet ground state, respectively. Similarly, the field dependence of M after photolysis of their complexes with Cu(hfac)(2) was measured in a frozen solution. A theoretical equation was used to fit the experimental M-H/T data for the Cu(hfac)(2) complexes with 1 and 2 to give spin quantum numbers S = 6.4 and 8.2, respectively. On the other hand, after photolysis of Cu(hfac), with 3 and 4, M-H plots clearly showed hysteresis loops with similar to 2 Oe coercive field. (C) 2001 Elsevier Science Ltd. All rights reserved.

引用

页码：1387 / 1389

页数：3

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