Abstract :
We have performed an ab initio study of the structure of polonium. By calculating total energies in a number of tetragonal lattice configurations, we have shown that the simple cubic structure is preferred by the system. The other two zero-stress structures, bcc and fcc, correspond to inflection points along this path. These calculations agree with experimental evidence that polonium is the only known element to assume the simple cubic structure at room temperature. We have found an LDA lattice constant of 3.28 إ, and we have obtained two of the elastic constants: C11=113 GPa and C12=28 GPa.
