Modeling and Determining the Averaged Binary Potential Fields of Five Noble Gases from Sound Speed

In terms of averaged interactive fields, this research discovered a new relation between averaged binary potential field (ABPF) and sound speed. Then, the ABPFs of five noble gases were modeled using an extended Lennard–Jones potential function. The derived equation based on the ABPF and the model potential accurately described the sound speed data of the five noble gases from the National Institute of Standards and Technology. Later, the surface of the ABPF was determined from the data, which indicated that the ABPF principally exhibited the conventional Lennard–Jones’ potential at low temperatures, but performed as a soft sphere potential at high temperatures. This temperature-based shift represents new knowledge regarding intermolecular interactions. The derived equation also provided a novel and practical method to calculate the sound speed from temperature and density.