Atomic-scale study of lattice defect formation due to electronic excitation in spinel-type oxide

采用先进的透射电子显微镜和分子动力学模拟方法，研究了快速重离子辐照下铝酸镁尖晶石化合物MgAl_2O_4在强电子激发下的结构失序，并探讨了其作为惰性基体材料在核工程中的应用。结果清楚地定量地揭示了离子轨道内部的原子结构和诱导的无序行为。还证明了转化为缺陷岩盐结构的原子机制。

Structural disordering in magnesium aluminate spinel compounds MgAl_2O_4 induced by strong electronic excitation due to irradiation with swift heavy ions were investigated by means of advanced transmission electron microscopy and molecular dynamics simulations, in connection to their application as inert matrix material in nuclear engineering. The results have clearly revealed the atomistic structure inside ion-tracks as well as the induced disordering behavior quantitatively. The atomistic mechanism for transformation into defective rock-salt structure has been also demonstrated.