Variational DVR Calculations

摘要

In the discrete variable representation (DVR) method the potential energy matrix ${cal V}$ has a particular simple form. It is diagonal with values of the interaction potential at the discrete points. However, this simple form is obtained by making approximations in the calculation of the matrix elements of ${cal V}$ . As a consequence the results cannot be considered as variational estimates. We will show how to recover the variational character of the method using the discrete variable representation eigenvectors as trial functions and performing a variational calculation in a restricted Hilbert space.