Bubble states of atoms in liquid helium

Abstract

The solvation of impurity atoms {Na, K, Rb, Cs, Mg, Ca, Sr, Ba} with small ionization energy in liquid helium is studied. It is shown that allowance for unmatched interaction of impurity atoms and helium atoms is important for determining the parameters of the atomic state. The size of the bubble state R0 is determined by the strong repulsion between helium atoms and valence electrons of impurity atoms. The R0 value is universal, and the expression 2R0/ν = const ≈ 11–13 depends weakly on the place of the impurity atom in the periodic table. The parameter ν is given by the impurity ionization energy J = 1/2ν2 (in atomic units); the ν value indicates the size of the impurity atom. An energy barrier that separates the bulk and surface atomic impurity states is determined.