Sun Weiwei, Luo Wei, Ahuja Rajeev
Department of Material Science and Engineering, KTH-Royal Institute of Technology, Stockholm SE-10044, Sweden.
Department of Physics and Astronomy, Uppsala University, Box 516, SE-75120 Uppsala, Sweden.
Sci Rep. 2015 Sep 4;5:13740. doi: 10.1038/srep13740.
Density functional theory has been applied to elucidate the stability of thorium monoxide (ThO). It is found out that the pressure can stabilize the rocksalt phase of ThO, and the transition pressure is estimated between 14 and 22 GPa. The stability of ThO can be attributed due to the gradually filling 5f orbitals at the expense of 7s and 6d electrons in Th metal. For ThO, the pressure induces stronger Th-O bond reflected by the newly established 6d-2p hybridization which is the dominant cause of its stability. The phonon dispersion curves of the rocksalt phase show the positive frequencies which indicates its dynamical stability. Our successful prediction of the stabilization of the metallic ThO has proposed a route to synthesize novel actinide monoxides.
密度泛函理论已被用于阐明一氧化钍（ThO）的稳定性。研究发现，压力可以使ThO的岩盐相稳定，过渡压力估计在14至22吉帕之间。ThO的稳定性可归因于Th金属中5f轨道逐渐填充，同时7s和6d电子减少。对于ThO，压力诱导形成更强的Th - O键，这通过新建立的6d - 2p杂化得以体现，这是其稳定性的主要原因。岩盐相的声子色散曲线显示出正频率，这表明其动力学稳定性。我们对金属态ThO稳定性的成功预测为合成新型锕系单氧化物提供了一条途径。
