INTERACTION POTENTIAL BETWEEN ATOMS OF He
Ivan Franko National University of LvivIn this work, the pair potential of interatomic interaction between helium atoms is established from first principles without using fitting parameters. Previously obtained from Schrodinger's equation, is the connection between the potential Fourier image and the coefficient functions. An expansion of the many-boson system ground state wave function logarithm by the 'degrees' of density fluctuations is used. RPA as the zero approximation and the approximation of 'two sums over wave vector' as the first one are considered. The results of this work have lead to the value of the first sound velocity bieng 231 m/s, while the experiment gives 237 m/s. The fit of our potential with the Aziz model potential is quite good: the well depths are -10.58 K and -11.04 K respectively.