μSR study of the superparamagnetic mesoscopic cluster Fe8

被引：6

作者：

Lascialfari, A ^{[1
]}

Carretta, P

Gatteschi, D

Sangregorio, C

Lord, JS

Scott, CA

机构：

[1] Univ Pavia, Dipartimento Fis A Volta, I-27100 Pavia, Italy

[2] Ist Nazl Fis Nucl, I-27100 Pavia, Italy

[3] Univ Florence, Dept Chem, I-50144 Florence, Italy

[4] Rutherford Appleton Lab, ISIS, Didcot OX11 0QX, Oxon, England

来源：

PHYSICA B | 2000年 / 289卷

关键词：

mesoscopic clusters; superparamagnetism; relaxation rate;

D O I：

10.1016/S0921-4526(00)00272-6

中图分类号：

O469 [凝聚态物理学];

学科分类号：

070205 ;

摘要：

Muon longitudinal relaxation rate (lambda) measurements as a function of temperature and magnetic field in Fe8 molecular clusters are presented. The temperature dependence of lambda is characterized by broad maxima centered at a temperature which increases with increasing field and with an intensity inversely proportional to the field itself. While smooth field dependence of lambda is observed in Fe8 : Br, in Fe8 : ClO4 the field dependence of lambda is anomalously strong below T = 2 K. In both types of Fe8 under particular magnetothermal cycling conditions, a muon precession signal was observed to set in in zero field for T < 2.2 K, suggesting the presence of a local field at the muon site associated with the freezing of the cluster magnetic moment. (C) 2000 Elsevier Science B.V. All rights reserved.

引用

页码：110 / 114

页数：5

共 15 条

[1] Superparamagnetic-like behavior in an octanuclear iron cluster [J].

Barra, AL ;

Debrunner, P ;

Gatteschi, D ;

Schulz, CE ;

Sessoli, R .

EUROPHYSICS LETTERS, 1996, 35 (02) :133-138

[2] DYNAMICS IN CANONICAL SPIN-GLASSES OBSERVED BY MUON SPIN DEPOLARIZATION [J].

CAMPBELL, IA ;

AMATO, A ;

GYGAX, FN ;

HERLACH, D ;

SCHENCK, A ;

CYWINSKI, R ;

KILCOYNE, SH .

PHYSICAL REVIEW LETTERS, 1994, 72 (08) :1291-1294

[3] MAGNETIC-PROPERTIES OF AN OCTANUCLEAR IRON(III) CATION [J].

DELFS, C ;

GATTESCHI, D ;

PARDI, L ;

SESSOLI, R ;

WIEGHARDT, K ;

HANKE, D .

INORGANIC CHEMISTRY, 1993, 32 (14) :3099-3103

[4] Macroscopic measurement of resonant magnetization tunneling in high-spin molecules [J].

Friedman, JR ;

Sarachik, MP ;

Tejada, J ;

Ziolo, R .

PHYSICAL REVIEW LETTERS, 1996, 76 (20) :3830-3833

[5] LARGE CLUSTERS OF METAL-IONS - THE TRANSITION FROM MOLECULAR TO BULK MAGNETS [J].

GATTESCHI, D ;

CANESCHI, A ;

PARDI, L ;

SESSOLI, R .

SCIENCE, 1994, 265 (5175) :1054-1058

[6] Proton NMR for measuring quantum level crossing in the magnetic molecular ring Fe10 [J].

Julien, MH ;

Jang, ZH ;

Lascialfari, A ;

Borsa, F ;

Horvatic, M ;

Caneschi, A ;

Gatteschi, D .

PHYSICAL REVIEW LETTERS, 1999, 83 (01) :227-230

[7] Proton NMR and μSR in Mn12O12 acetate:: A mesoscopic magnetic molecular cluster [J].

Lascialfari, A ;

Gatteschi, D ;

Borsa, F ;

Shastri, A ;

Jang, ZH ;

Carretta, P .

PHYSICAL REVIEW B, 1998, 57 (01) :514-520

[8] Thermal fluctuations in the magnetic ground state of the molecular cluster Mn12O12 acetate from μSR and proton NMR relaxation [J].

Lascialfari, A ;

Jang, ZH ;

Borsa, F ;

Carretta, P ;

Gatteschi, D .

PHYSICAL REVIEW LETTERS, 1998, 81 (17) :3773-3776

[9] Local field dynamics in a resonant quantum tunneling system of magnetic molecules [J].

Ohm, T ;

Sangregorio, C ;

Paulsen, C .

EUROPEAN PHYSICAL JOURNAL B, 1998, 6 (02) :195-199

[10] Non-exponential relaxation in a resonant quantum tunneling system of magnetic molecules [J].

Ohm, T ;

Sangregorio, C ;

Paulsen, C .

JOURNAL OF LOW TEMPERATURE PHYSICS, 1998, 113 (5-6) :1141-1146

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