Abstract:

 An investigation on structural transformation, electronic and elastic properties of Ge under high pressure was conducted via first\|principles calculations based on density functional theory (DFT) with the plane wave basis set. The results show that  first\|order structural transformation from the cubic diamond (Ge-Ⅰ) to β-Sn structure (Ge-Ⅱ) occurs at 9.0 GPa. The electric conductivity of material was  transformed, that is,  from that of  semiconductor to that of conductor. The  elastic coefficient of Ge-Ⅰ shows a linear relation with  pressure. 

Key words: first-principles calculations, structural transformation, high pressure, elastic properties