Preparing the input files
CHAMP needs the following input files to describe a system
- Molecular coordinates
 - ECP / Pseudopotentials
 - Basis Set (Radial Grid files)
 - Basis pointers
 - MO coefficients
 - Determinants and/or CSF files
 - Molecular orbital symmetries (Optional)
 - Molecular orbital eigenvalues (Optional)
 - Jastrow parameters file
 - Jastrow derivative parameters file (Optional)
 
CHAMP input file itself has a modular structure. For example,
1. general
2. electrons
3. blocking_vmc
4. blocking_dmc
5. optwf
6. ...
A typical input file looks like:
%module general
    title        'butadiene'
    pool         'pool/'
    pseudopot    BFD
    basis        BFD-T
    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    TZ_1M_5k.det
load orbitals        champ_v3_ci1010_pVTZ_1_orbitals.lcao
load symmetry        champ_v3_ci1010_pVTZ_1_symmetry.sym
load jastrow         jastrow_good_b3lyp.0
load jastrow_der     jastrow.der
%module electrons
    nup           11
    nelec         22
%endmodule
%module optwf
    ioptwf        1
    ioptci        1
    ioptjas       1
    ioptorb       1
    method        'sr_n'
    multiple_adiag 0
    ncore         0
    nextorb       280
    no_active     0
    nblk_max      100
    nopt_iter     1
    sr_tau        0.025
    sr_eps        0.001
    sr_adiag      0.01
    isample_cmat  0
    energy_tol    0.0
%endmodule
%module blocking_vmc
    vmc_nstep     20
    vmc_nblk      100
    vmc_nblkeq    1
    vmc_nconf_new 0
%endmodule
Table of contents
- Using TREXIO as input
 - Molecular Coordinates
 - Pseudopotentials
 - Basis on the grid
 - Basis pointers
 - Molecular Orbitals
 - Determinants / CSFs
 - MO symmetries
 - MO Eigenvalues
 - Jastrow
 - Jastrow Derivatives