The VIBSTATE program allows to specify the occupation number vectors for individual vibrational states to be calculated in the following vibrational SCF and vibration correlation programs. Within the input stream, the VIBSTATE program needs to be called prior to the first call of the VSCF program. Note that, the VIBSTATE program needs only to be called, if a limited number of states shall be computed. On the contrary, the COMBI keyword within the VSCF and VCI programs generate large lists of vibrational states, which may result in significant computational effort. The VIBSTATE program necessarily requests the VSTATE directive to be called as described below. If only those vibrational states shall be computed, which are defined by the VIBSTATE program, all subsequent programs need to call the USERMODE option.