Ground-state potential energy curves of LiHg,NaHg,and KHg revisited

摘要

We present the results of large-scale CCSD(T) calcualtions on the potential energy curves for the ground states of LiHg,NaHg,and KHg.In these calcualtions,the Hg~(20+) core is simulated by a pseudopotential which has been adjusted to reproduce experimental excitation and ionization energies of the Hg atom at the coupled-cluster level.Moreover,we apply a weighted multiproperty fitting procedure to determine relaible potentials for LiHg,NaHg,and KHg which reproduce the available experimental results.In the case of LiHg,this best-fit potential is based solely on experimental data and its agreement with our calcualted potential supports our computational procedure.For NaHg and KHg the experimental data had to be complemented by theoretical results in order to fix a best-fit potential.Our potentials and those proposed previously are evaluated by comparing calcualted scattering cross sections and vibrational energy levels with the available experimental data.