Slow magnetic relaxation of [Et3NH]2[Mn(CH3CN)4(H2O)2] [Mn10O4(biphen)4Br12] (biphen=2,2′-biphenoxide) at very low temperature

被引：42

作者：

Barra, AL

Caneschi, A

Gatteschi, D

Goldberg, DP

Sessoli, R

机构：

[1] Univ Florence, Dept Chem, Florence, Italy

[2] CNRS, Grenoble High Magnet Field Lab, F-38042 Grenoble, France

[3] Johns Hopkins Univ, Dept Chem, Baltimore, MD 21218 USA

来源：

JOURNAL OF SOLID STATE CHEMISTRY | 1999年 / 145卷 / 02期

关键词：

D O I：

10.1006/jssc.1999.8185

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The high-field EPR spectra of a mixed valence cluster compound of formula [Et3NH](2)[Mn(CH3CN)(4)(H2O)(2)] [Mn10O4 (biphen)(4)Br-12] confirm that the high-spin ground state (S = 12) of the cluster has a negative zero-field splitting, D = - 0.037(1) cm(-1). The reversal of the magnetization at low temperature should therefore overcome an energy barrier corresponding to \D\S-2 which corresponds to ca. 7.7 K. Slow relaxation of the magnetization is detected below 1 K by ac magnetic susceptibility and the characteristic time follows approximately an Arrhenius law, where the height of the barrier is 7.0 K. The counterion, constituted by a manganese(II) complex, is easily oxidized, and aged samples seem to contain amorphous Mn3O4. (C) 1999 Academic Press.

引用

页码：484 / 487

页数：4

共 20 条

[1] Resonant magnetization tunneling in the trigonal pyramidal Mn(IV)Mn-3(III) complex [Mn4O3Cl(O2CCH3)3(dbm)3] [J].