Microscopic theory of the static structural properties and phase transformation of Ge

Using the atomic number as the only input, the static structural properties and the pressure-induced phase transformation of Ge are calculated within an ab initio density-functional pseudopotential scheme. Among a set of likely crystal structures, the diamond structure is found to be the most stable. The calculated lattice constant, cohesive energy, and bulk modulus are in excellent agreement with experiment, and the properties of the phase transformation to the β-tin structure under pressure accurately reproduced.