Energy-barrier enhancement by ligand substitution in tetrairon(III) single-molecule magnets

被引:118
作者
Cornia, A
Fabretti, AC
Garrisi, P
Mortalò, C
Bonacchi, D
Gatteschi, D
Sessoli, R
Sorace, L
Wernsdorfer, W
Barra, AL
机构
[1] Univ Modena, Ctr SCS, Dipartimento Chim, UdR INSTM, I-41100 Modena, Italy
[2] Univ Florence, Polo Sci Univ, UdR INSTM, Dipartimento Chim, I-50019 Sesto Fiorentino, Italy
[3] CNRS, Lab Louis Neel, F-38042 Grenoble, France
[4] CNRS, Lab Champs Magnet Intenses, F-38042 Grenoble 9, France
关键词
cluster compounds; iron; magnetic properties; single-molecule magnets; tripodal ligands;
D O I
10.1002/anie.200352989
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
A relaxing time: A dramatic increase of the energy barrier (U eff) in tetrairon(III) single-molecule magnets can be achieved by simple chemical modification. Site-specific replacement of the six methoxide bridges in [Fe4(OMe)6(dpm)6] (Hdpm = dipivaloylmethane; Ueff/ kB = 3.5 K) with two tripodal 1,1,1-tris-(hydroxymethyl)ethane (H3thme) ligands affords the compound [Fe4(thme)2(dpm)6] (see figure) with Ueff/kB = 15.6(2) K and a magnetic relaxation time exceeding 1000 s below 0.2 K.
引用
收藏
页码:1136 / 1139
页数:4
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