An analytical formula For He-Ne Van der Waals potential without any adjustable parameters

•An analytical formula without any adjustable parameters for the heteronuclear dimers potential is derived.•The interaction potential of HeNe calculated by the proposed formula in very good agreement with the accurate results.•The present method also can be applied to other heteronuclear dimers.

A simple analytical formula for the entire van der Waals potential of the He-Ne dimer is derived. The short range repulsive part is essentially from the surface integral theory with the parameters calculated by a combining rule. The long range attractive potential is described by the damped asymptotic dispersion series. The potential depends only on the known dispersion coefficients and the amplitude of the asymptotic wave function and the ionization energy of the atoms. Without any adjustable parameters the HeNe potential predicted with the present formula is in excellent agreement with the accurate experimental and theoretical results around the equilibrium distance and long range distances. The same method also can be applied to other heteronuclear dimers.