Effect of pressure on the magnetic anisotropy in the single-molecule magnet Mn12-acetate: an inelastic neutron scattering study.
Effect of pressure on the magnetic anisotropy in the single-molecule magnet Mn12-acetate: an inelastic neutron scattering study.
复制标题
压力对单分子磁铁 Mn12-醋酸盐磁各向异性的影响：非弹性中子散射研究。
DOI：
10.1002/anie.200500171
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发表时间：
2005
影响因子：
--
通讯作者：
H. Güdel
中科院分区：
文献类型：
--
作者：
A. Sieber;R. Bircher;O. Waldmann;G. Carver;G. Chaboussant;H. Mutka;H. Güdel
Mn 12-acetate是一类多核过渡金属配合物的原型，称为单分子磁体（SMM）。这些自旋团簇表现出新的现象，如低温下的慢弛豫和磁化量子隧穿（QTM），[1，2]大约十年前的这一发现引发了物理和化学领域的一系列跨学科研究。Mn 12-acetate是第一个被发现的SMM，它的性质已经通过许多不同的技术进行了深入的研究。如图1所示，它由氧配位的Mn 4+离子的四面体核心组成，该四面体核心被具有氧代和乙酸根配位的八个Mn 3+离子的环包围。[3]Mn ~（4+）和Mn ~（3+）离子之间的反铁磁相互作用导致S= 10基态。[4]Mn 3+配位环境是Jahn-Teller扭曲的;图1中强调了伸长的Mn 2 O键。由此产生的Mn 3+单离子各向异性的协同作用导致S= 10团簇基态的整体易轴型各向异性，其可以由等式（1）表示。
Mn12-acetate is the prototype of a class of polynuclear transition metal complexes known as single-molecule magnets (SMMs). These spin clusters exhibit new phenomena such as slow relaxation and quantum tunneling of magnetization (QTM) at low temperature,[1, 2] and this discovery, about a decade ago, triggered a flurry of interdisciplinary research in physics and chemistry. Mn12-acetate was the first SMM discovered, and its properties have been thoroughly studied by many different techniques. As shown in Figure 1, it is composed of a tetrahedral core of oxygen-coordinated Mn4+ ions, which are surrounded by a ring of eight Mn3+ ions with oxo and acetate coordination.[3] Dominant antiferromagnetic interactions between the Mn4+ and Mn3+ ions lead to an S= 10 ground state.[4] The Mn3+ coordination environment is Jahn–Teller-distorted; the elongated MnÀO bonds are emphasized in Figure 1. The concerted action of the resulting Mn3+ single-ion anisotropies leads to an overall easy-axis-type anisotropy of the S= 10 cluster ground state, which can be expressed by Equation (1).