21.4.3 Projected excited state calculations

PROJECT,record,nprojc;

Initiate or continue a projected excited state calculation, with information stored on record. If nprojc$>0$, the internal CI vectors of nprojc previous calculations are used to make a projection operator. If nprojc$= -1$, this calculation is forced to be the first, i.e. ground state, with no projection. If nprojc$=0$, then if record does not exist, the effect is the same as nprojc$= -1$; otherwise nprojc is recovered from the dump in record. Thus for the start up calculation, it is best to use project,record,-1; for the following excited calculations, use project,record; At the end of the calculation, the wavefunction is saved, and the information in the dump record updated. The project card also sets the tranh option, so by default, transition hamiltonian matrices are calculated.

For example, to do successive calculations for three states, use

ci;...;project,3000.3,-1;
ci;...;project,3000.3;
ci;...;project,3000.3;