Beyond 150 GPa, slope of melting in our determination is trending to slow down. The values of present study in pressure range are smaller than those of shock-compression melting experiments by Nguyen and Holmes [9], Brown and McQueen [7]. There are some reasons which can simply explain this difference: (i) the limitation of Lindemann's criterion approach; (ii) not really best-fitted parameter q as well as pressure-dependent Grüneisen expressions (4); (iii) the lack of consideration of electron configuration of metal [17].