HfN结构相变及热力学性质的第一性原理研究  

Study on first principles of phase transition and thermodynamic properties of HfN

作　　者：谭心[1] 祁晖[1] 贾亦超 李璇[1] 

机构地区：[1]内蒙古科技大学机械工程学院,内蒙古包头014010 [2]天津航天长征火箭制造有限公司,天津300642

出　　处：《内蒙古科技大学学报》2017年第2期110-114,共5页Journal of Inner Mongolia University of Science and Technology

基　　金：内蒙古自然科学基金(2015MS0550);内蒙古自治区高等学校科学研究项目(NJZY153);包头市重大科技发展项目(2012Z1006-2)

摘　　要：采用基于密度泛函理论的第一性原理方法对HfN的结构稳定性、力学性质、声子色散关系和热力学性质进行了研究.通过计算焓压关系、声子谱和弹性性质,得知常压下NaCl结构比CsCl结构更稳定.HfN由NaCl结构到CsCl结构的相变发生在177~200 GPa之间.同时对NaCl-HfN的热力学性质进行了分析,结果表明:一定温度下,等体热容、热膨胀系数和格乃森参数均随温度增加而增大.Structural stability, mechanical properties,phonon dispersion relations and thermodynamic properties of HfN was investigated by using the first-principle method based on the density-functional theory （DFF）. Enthalpy-pressure relation, phonon spectrum and e- lastic properties show that NaC1 structure is more stable compared with the CsC1 structure at atmospheric pressure. The phase transition of HfN to CsC1 structure from NaC1 structure occurred between 177 GPa and 200 GPa. The thermodynamic properties of NaC1-HfN was analysed. The results show that heat capacity, thermal expansion coefficient and Genaisen parameters increase with increasing the tem- perature under certain pressure.

关 键 词：第一性原理 HfN 相变 热力学性质 

分 类 号：O482[理学—固体物理]