Abstract Mainly on the basis of the various crystal properties the potential energy of interaction of krypton on a six-parameter model has been obtained. The potential energy curve thus obtained is more logical than those on the usual two or three parameter models (e.g. exp-6, L-J (6–12) etc.). It has been found that the force constants on the L-J (6–12) model derived from the constants on the six-parameter model can correlate the various transport and the equilibrium properties of krypton with reasonable success. This result is in contradiction to the results obtained recently by Mason from an analysis of the transport properties data only.