source: ThirdParty/mpqc_open/src/bin/mpqc/validate/mbpt/mbpt_mp2mem_c1.in

% molecule specification
molecule<Molecule>: (
  symmetry = C1
  angstroms = yes
  { atoms geometry } = {
     C [  0.0000   1.0094   0.0000 ]
     C [  0.0000  -1.0094   0.0000 ]
     H [  0.9174   1.6662   0.0000 ]
     H [ -0.9174  -1.6662   0.0000 ]
     H [  0.9174  -1.6662   0.0000 ]
     H [ -0.9174   1.6662   0.0000 ]
  }
)
% basis set specification
basis<GaussianBasisSet>: (
  name = "3-21G"
  molecule = $:molecule
)
mpqc: (
  savestate = no
  restart = no
  do_energy = yes
  do_gradient = no
  % method for computing the molecule's energy
  mole<MBPT2>: (
    molecule = $:molecule
    basis = $:basis
    memory = 16000000
    nfzc = 2
    nfzv = 2
    method = mp
    algorithm = memgrp
    reference<CLHF>: (
      molecule = $:molecule
      basis = $:basis
      memory = 16000000
    )
  )
)