Low temperature specific heat of molecular nanomagnets and the contribution of the internal fields

被引：10

作者：

Gomes, AM ^{[1
]}

Novak, MA ^{[1
]}

Nunes, WC ^{[1
]}

Rapp, RE ^{[1
]}

机构：

[1] Univ Fed Rio de Janeiro, Inst Fis, BR-21945970 Rio De Janeiro, Brazil

来源：

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS | 2001年 / 226卷 / PART II期

关键词：

magnetic relaxation; specific heat; magnetization-quantum tunneling;

D O I：

10.1016/S0304-8853(01)00094-4

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We present the specific heat measurements at very low temperatures of the single molecule magnets Mn(12)ac and Fe-8. Below 3 K, both systems present superparamagnetic blocking effects in zero external magnetic field and an excess specific heat contribution around 1 K. The experimental results are explained considering a distribution of internal fields of dipolar and hyperfine origin as well as quantum tunneling of the magnetization. (C) 2001 Elsevier Science B.V. All rights reserved.

引用

页码：2015 / 2017

页数：3

共 7 条

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