The moderate-pressure elastic properties of potassium halides KX (X=F, Cl, Br) was studied theoretically using the density functional theory (DFT) with normconserving pseudopotentials method. The phase transformat...The moderate-pressure elastic properties of potassium halides KX (X=F, Cl, Br) was studied theoretically using the density functional theory (DFT) with normconserving pseudopotentials method. The phase transformation from the B1 phase (NaCl-type structure) to the denser B2 phase (CsCl-type structure) occurred at 7.7, 3.46 and 2.96 GPa for KF, KCI and KBr, respectively. The elastic stiffness coefficients and bulk modulus of these materials were calculated as function of hydrostatic pressure and compared with both the experimental and theoretical values.展开更多
文摘The moderate-pressure elastic properties of potassium halides KX (X=F, Cl, Br) was studied theoretically using the density functional theory (DFT) with normconserving pseudopotentials method. The phase transformation from the B1 phase (NaCl-type structure) to the denser B2 phase (CsCl-type structure) occurred at 7.7, 3.46 and 2.96 GPa for KF, KCI and KBr, respectively. The elastic stiffness coefficients and bulk modulus of these materials were calculated as function of hydrostatic pressure and compared with both the experimental and theoretical values.