Passing dynamic objects by reference in Fortran 90: application to time-dependent quantum chemistry

A new effective strategy of passing large variable size objects to subroutines and back in fortran 90 is described. The objects are passed by reference utilizing user-defined pointer type variables declared in a shared module. The efficiency of the developed approach is demonstrated by applying it to program the analytic solution for action of the powers of Hamiltonian on the Hermite polynomial type basis function.