摘要
The density functional calculations of the energy band structure and density of state for the tetragonal PbO-type phase a-FeSe and hexagonal NiAs-type phase β-FeSe are reported in this paper. The structural phase transition from tetragonal to hexagonal FeSe under high pressure is investigated, it is found that the calculated transition pressure for the a→β- phase transformation is 8.5 GPa, Some fluctuations in the transition pressure maybe occurred by different external factors such as temperature and stress condition. There is about 17% volume collapse accompanying the α→β- phase transformation.
The density functional calculations of the energy band structure and density of state for the tetragonal PbO-type phase a-FeSe and hexagonal NiAs-type phase β-FeSe are reported in this paper. The structural phase transition from tetragonal to hexagonal FeSe under high pressure is investigated, it is found that the calculated transition pressure for the a→β- phase transformation is 8.5 GPa, Some fluctuations in the transition pressure maybe occurred by different external factors such as temperature and stress condition. There is about 17% volume collapse accompanying the α→β- phase transformation.
基金
supported by the National Natural Science Foundation of China (Grant No. 61072028)
the Key Science and Technology Program of Guangdong Province of China (Grant No. 2010B010800028)
the Natural Science Foundation of Guangdong Province of China (Grant No. 10151063101000048)
