A Systematic Investigation on Magnetism and Phase Stability of Cobalt

作者：Kuang Fang Guang; Kuang Xiao Yu^*; Kang Shu Ying

来源：Zeitschrift fur Naturforschung Section A-A Journal of Physical Sciences, 2014, 69(5-6): 254-262.

DOI：10.5560/ZNA.2014-0024

• First-Principles
• Magnetism
• Phase Transition
• Cobalt

Using the first-principles plan-wave pseudo-potential method, a systematic investigation on structural property, magnetism, and pressure-induced phase transitions of cobalt is carried out. Cobalt with four hcp (alpha), fcc (beta), bcc (gamma), and epsilon (epsilon) phases both in ferromagnetic (FM) and nonmagnetic (NM) states is considered. Issues of fitting equation of states in the energy volume data points containing magnetism are discussed. Our results reveal two stable phase transition points, namely, from FM beta-phase to FM alpha-phase at 28.2 GPa and from FM alpha-phase to NM beta-phase at 123.7 GPa, which are consistent with previous experimental predictions. The meta-stable magnetic transformation points from FM to NM state for alpha,beta, and E structures are 135.7 GPa, 84.0 GPa, and 168.7 GPa, respectively. Furthermore, both FM y-phase and FM e-phase undergo a meta-stable transformation to NM beta-phase at 25.0 GPa and 42.3 GPa, respectively.

• 出版日期2014-6
• 单位四川大学