Compact Molecule of Beryllium

The interaction potential for beryllium atoms is calculated using the Ritz variational method with molecular wave functions as trial functions. The results of calculations for Be₂ molecules in the ¹_g ⁺ state, which from the well–known data is considered ground, coincide with the results of previous studies. Similar calculations for the ³_u ⁺ state show that the minimum energy for this state is reached at horter internuclear distance and is lower than that for the ¹_g ⁺ state.