Magnetocaloric effect in spin-degenerated molecular nanomagnets

被引：77

作者：

Evangelisti, M. ^{[1
]}

Candini, A. ^{[1
]}

Affronte, M. ^{[1
,2
]}

Pasca, E. ^{[3
]}

de Jongh, L. J. ^{[3
]}

Scott, R. T. W. ^{[4
]}

Brechin, E. K. ^{[4
]}

机构：

[1] CNR INFM, Natl Res Ctr nanoStruct & bioSyst Surfaces, I-41100 Modena, Italy

[2] Univ Modena & Reggio Emilia, Dipartimento Fis, I-41100 Modena, Italy

[3] Leiden Univ, Kamerlingh Onnes Lab, NL-2300 RA Leiden, Netherlands

[4] Univ Edinburgh, Sch Chem, Edinburgh EH9 3JJ, Midlothian, Scotland

来源：

PHYSICAL REVIEW B | 2009年 / 79卷 / 10期

关键词：

entropy; magnetic cooling; manganese; molecular magnetism; nanomagnetics; nanostructured materials; spin dynamics; MAGNETIC REFRIGERATION; CLUSTERS;

D O I：

10.1103/PhysRevB.79.104414

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

For molecular nanomagnets, excesses of magnetic entropy at finite low temperatures are induced by degrees of freedom resulting from macroscopic degeneracies of the molecular spin states. We experimentally demonstrate that this effect can be huge and efficiently exploited for enhancing the magnetic field dependence of the adiabatic temperature change. We specifically consider the Mn(32) molecular nanomagnet, proving it to be an excellent magnetic refrigerant below T approximate to 2 K, due almost entirely to its spin degeneracy.

引用

页数：5

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