Dimensions of heterogeneous clusters formed during condensation of Ar–Kr mixtures in supersonic jet

The average number of atoms in mixed atomic clusters formed during the adiabatic expansion of Ar–Kr mixtures with various compositions into vacuum has been determined using the method of electron diffraction. A previously unreported phenomenological relation between the average cluster size and the total pressure and temperature of a gas mixture at the input of a supersonic nozzle has been found. This relation has a rather general character and can be applied to other binary clusters of atomic and molecular gases. A method is proposed for establishing the boundaries of existence of the homogeneous and heterogeneous clusters depending on the pressure, temperature, and composition of gas mixtures.