Butadiene VMC with SDT Excitations¶

This tutorial involves a VMC optimization calculation on Butadiene using a wavefunction that includes Singles, Doubles, and Triples (SDT) excitations (1522 determinants).

Input File Setup¶

Input File: vmc_optimization_1522.inp

%module general
    title        'butadiene'
    mode         vmc_one_mpi
%endmodule

load molecule        $pool/champ_v3_butadiene.xyz
load basis_num_info  $pool/champ_v3_BFD-T_basis_pointers.bfinfo

load determinants    champ_v2_gamess_ci1010_SDT_pVTZ_determinants.det
load orbitals        champ_v3_trexio_order_champ_v2_gamess_ci1010_SDT_pVTZ_orbitals.lcao
load jastrow         jastrow_good_b3lyp.0
load jastrow_der     jastrow.der
load symmetry        champ_v2_gamess_ci1010_SDT_pVTZ_symmetry.sym

%module optwf
    ioptwf        1
    ioptci        1       # Optimize CI coefs
    ioptjas       1       # Optimize Jastrow
    ioptorb       1       # Optimize Orbitals
    method        'sr_n'
    nopt_iter     1
%endmodule

Significance¶

This test verifies the stability and performance of the optimization algorithm (sr_n) when handling higher-order excitations (Triples) in the determinant expansion.

Resources: Butadiene SDT Test