Excited-state Coupled Cluster methods

 module EOM

This module contains the implementation of the EOM (Equation of Motion) methods for computing the excited states.

calc_svd_eom(EC::ECInfo, method::ECMethod)

Calculate decomposed closed-shell EOM-DCSD.

Currently only DC methods are supported. DF integrals are used (have to be calculated before).

calc_R2_df_cis_pert_d(EC::ECInfo, U1)

Calculates doubles residuals for CIS(D) with dressed integrals.

calc_eom_svd_au(EC::ECInfo, U1, U2, st)

Calculate singles and doubles AUs for SVD-EOM-DCSD.

cis_HU1(EC::ECInfo, U1)

Compute H times U1 for CIS.

$V^i_a = f_a^c U^i_c - f_k^i U^k_a + (2 v_{ak}^{ic} - v_{ak}^{ci}) U^k_c$

cis_homo_lumo_guess(EC, nstates)

generate a CIS starting guess for nstates by preparing a CIS matrix around the HOMO-LUMO and diagonalizing it

df_cis_HU1(EC::ECInfo, U1)

Compute H times U1 for CIS with density fitting.

df_cis_homo_lumo_guess(EC, nstates)

generate a CIS starting guess for nstates by preparing a CIS matrix around the HOMO-LUMO and diagonalizing it

df_new_singles_trial(EC, R1, omega, shift)

Calculate new singles trial vector with density fitting.

new_doubles_trial!(Vec2, ϵo, ϵv, omega, shift)

Calculate new doubles trial vector.

Updates the vector in place.

new_singles_trial!(Vec1, ϵo, ϵv, omega, shift)

Calculate new singles trial vector.

Updates the vector in place.

new_singles_trial(EC, R1, omega, shift)

Calculate new singles trial vector.

new_trial_vector!(EC, vecs, omega)

Calculate new trial vector using residuals from vecs.

Updates the vector in place.