Cohesive properties of Ge,Si and Diamond calculated with minimum basis sets.

We present ab initio calculations of the cohesive properties of Ge, Si and Diamond. Electron-electron interactions are treated within the Local Density Functional approximation and electron-ion interactions are described by Norm-conserving Pseudopotentials. The wavefunctions are expanded in local Gaussian orbitals. Acceptable results for equilibrium lattice constant, bulk modulus and cohesive energy are obtained with few (8-12) Gaussian functions per atom.