A method is developed for treating the error in the energy of a variation function as a perturbation, the variation function serving to describe the "unperturbed state." An effective potential is defined from the variation function, and comparison of this with the correct potential for the helium atom gives useful information about the behavior of the variation functions as the electronic separation approaches zero. In the second section, iterative methods of improving a variational wave function without increasing the number of parameters are discussed and the conditions under which they will be applicable are examined.
|Number of pages||4|
|Journal||The Journal of Chemical Physics|
|Publication status||Published - 1958|