It is shown that for wave functions of the form Ψ = Σk Ck exp (-Qk), where Qk is any positive definite quadratic form in the Cartesian co-ordinates of n particles and Ck a constant, all integrals ...

An approximate wave function expressed in terms of exponential functions, spherical harmonics, etc., with numerical coefficients has been calculated for the ground state of the beryllium atom. Judged ...