Low-lyingD1states of Be I

Abstract

The composition of the three lowest ${}_{}{}^1{}_{}{}^{}D$ states of BeI has been investigated using the multiconfiguration Hartree-Fock method. Though the $2p^2$ configuration lies above the $2s4d$ configuration in the Hartree-Fock approximation, correlation in the localized $2p^2$ configuration and its interaction with the higher-lying Rydberg series, including the continuum, are such that the $2p^2$ state is depressed to the extent that the lowest ${}_{}{}^1{}_{}{}^{}D$ state is predominately $2p^2$, the second largely $2s3d$, and the third almost entirely $2s4d$.