25.3 Options for EOMPRINT card

The following print options are mostly for testing purposes and for looking for the convergence problems.

EOMPRINT, key1=value1, key2=value2,...

where the following keywords key are possible:

DAVIDSON=ipr

Information about Davidson procedure:
ipr=1 print results of each "small diagonalization"
ipr=2 also print warning information about complex eigenvalues
ipr=3 also print hamiltonian and overlap matrix in trial space.

DIAGONAL=ipr

Information about configurations:
ipr=1 print the lowest approximate diagonal elements of the transformed hamiltonian
ipr=2 print orbital labels of important configurations
ipr=3 print all approximate diagonal elements
ipr=4 also print the long form of above.

PSPACE=ipr

Print information about the initial approximate hamiltonian:
ipr=2 print the approximate hamiltonian used to find the first approximation.

HEFF=ipr

Print information about effective Hamiltonian:
ipr=2 print columns of effective hamiltonian and overlap matrix in each iteration

RESIDUUM=ipr

Print information about residual vectors:
ipr=-1 no print in iteration
ipr=0 print energy values + residuum norm (squared) for each iteration (default)
ipr=1 also print warning about complex eigenvalue, and a warning when no new vectors is added to the trial space due to the too small norm of the residuum vector.
ipr=2 also print how many vectors are left

LOCEOM=ipr

ipr=1 prints overlaps of sample and tested vectors in each iteration, if FOLLOW card is present. Increasing ipr switches on more and more printing, mostly related to the local EOM-CCSD method.

POPUL=ipr

if ipr=1, do a population analysis of the singles part of the rhs EOM-CCSD wave function. By default the Löwdin method is used. The Mulliken analysis can be forced by adding MULLPRINT=1 to EOM card. Note that a more correct (but more expensive) approach is to calculate and analyse the EOM-CCSD density matrix, see section 25.1.

INTERMED=ipr

Print intermediates dependent on ground state CCSD amplitudes:
ipr=0 no print (default)
ipr=1 print newly created intermediates
ipr=2 also print more intermediates-related information