FCI(1)

NAME
fci - | Quantum Package > Selected Full Configuration Interaction with stochastic selection and PT2.

This program performs a CIPSI-like selected CI using a stochastic scheme for both the selection of the important Slater determinants and the computation of the PT2 correction. This CIPSI-like algorithm will be performed for the lowest states of the variational space (see determinants n_states). The FCI program will stop when reaching at least one the two following conditions:

•   number of Slater determinants > determinants n_det_max

•   abs(PT2) less than perturbation pt2_max

    The following other options can be of interest:

determinants read_wf
    When set to false, the program starts with a ROHF-like Slater determinant as a guess wave function. When set to true, the program starts with the wave function(s) stored in the EZFIO directory as guess wave function(s).

determinants s2_eig
    When set to true, the selection will systematically add all the necessary Slater determinants in order to have a pure spin wave function with an \widehat{S^2} value corresponding to determinants expected_s2.

    For excited states calculations, it is recommended to start with cis or cisd guess wave functions, eventually in a restricted set of MOs, and to set determinants s2_eig to true.

    Needs:

•   psi_coef

•   is_zmq_slave

•   do_pt2

•   mo_two_e_integrals_in_map

•   psi_det

    Calls:

•   run_cipsi()

•   run_slave_cipsi()

•   run_stochastic_cipsi()

    Touches:

•   ci_electronic_energy

•   ci_electronic_energy

•   ci_energy

•   ci_electronic_energy

•   n_det

•   n_iter

•   psi_occ_pattern

•   c0_weight

•   distributed_davidson

•   psi_coef

•   psi_det_sorted_bit

•   psi_det

•   psi_det_size

•   psi_det_sorted_bit

•   psi_energy

•   psi_occ_pattern

•   psi_energy

•   pt2_e0_denominator

•   pt2_match_weight

•   pt2_stoch_istate

•   read_wf

•   selection_weight

•   state_average_weight

•   threshold_generators

•   variance_match_weight

AUTHOR
A. Scemama, E. Giner

COPYRIGHT
2019, A. Scemama, E. Giner