An ab initio pseudopotential study of MnPo (M = Cu, Ag, Au;: n=1, 2) systems

The small coinage-metal polonium compounds MPo and M2Po, (M = Cu, Ag, Au) are studied at Hartree-Fock (HF), second-order Moller-Plesset perturbation theory (MP2), and coupled cluster method CCSD(T) levels using relativistic and non-relativistic pseudopotentials. The calculated geometries indicate that the M2Po (M = Cu, Ag, Au) systems have bent structures of similar to 64 degrees angles. Electron correlation corrections to the bond length M - Po are extremely small, but to the bond angle M - Po - M are significant; in general, it was reduced from 86 degrees to 64 degrees. Relativistic effects on bond angle are small, but on bond length are distinct. Both electron correlation effects and relativistic effects are essential to determine the geometry and relative stability of the systems. It can be predicted that Au2Po is relatively stable compared with Ag2Po.