Materials Science of Antiperovskites

为了开发各种智能材料，研究了具有反钙钛矿结构的化合物Mn3AX(A=过渡金属；X=轻元素，如N)的磁结构关联物理。在四方形变的反钙钛矿Mn3SbN中发现了高达1000ppm的超磁致伸缩。尽管Mn3AgN具有整体的金属特性，但在其温度-电阻率曲线上也发现了一个宽的极大值。利用具有巨大负热膨胀性能的反钙钛矿氮化锰制备了热膨胀可调的金属基或塑料基复合材料。所得到的复合材料的热膨胀是广泛可调的，甚至是负的。从磁结构和局部结构反常的关系出发，探讨了锰反钙钛矿巨负热膨胀的物理背景。

Physics of magnetostructural correlations in compounds with antiperovskite structure Mn3AX (A=transitional metals; X=light elements such as N) have been investigated, in order to develop various kinds of smart materials. Giant magnetostriction up to 1000 ppm was discovered in tetragonally distorted antiperovskite Mn3SbN. A broad maximum in the temperature-resistivity curve was also discovered in Mn3AgN, despite its overall metallic character. Thermal expansion adjustable metal or plastic matrix composites were fabricated using antiperovskite manganese nitrides exhibiting giant negative thermal expansion. Thermal expansion of the obtained composites is widely tunable, even negative. The physical background of the giant negative thermal expansion in the manganese antiperovskites was also explored in terms of the relation to the magnetic structure and the local structure anomaly.