Relativistic and electron correlation corrections to geometric structures and stabilities of dimers (M_2Te)_2, (M=Au,Ag,Cu)

The influences of relativistic and electron correlation effects on geometric structures and stabilities of dimers (M_2Te)_2, (M=Au,Ag,Cu), are studied at the HF and MP2 theoretical levels, using relativistic and non-relativistic pseudo-potentials. The results show that the electron correlation effect shorten the bond distances, increase the vibrational frequencies, decrease the energy and make the dimers trend to more compact and rigidity. The relativistic effects strengthen the intensity of them, and make the dimers more stable.