source: ThirdParty/mpqc_open/src/bin/mpqc/validate/ckpt/ckpt_0efcopt.in

% molecule specification
molecule<Molecule>: (
  symmetry = C1
  angstroms = yes
  { atoms geometry } = {
    N     [     0.51607603     0.04519735    -0.95614194 ]
    H     [    -0.19547589     0.17839942    -1.65845361 ]
    C     [     0.03095251    -0.69526932     0.25445565 ]
    C     [    -0.06456519     0.77121302     0.60822996 ]
    H     [     0.85374037     1.04857415    -0.32020191 ]
    H     [    -0.88816493    -1.22489056     0.08294898 ]
    H     [     0.79530751    -1.28353418     0.71918150 ]
    H     [    -1.04787041     1.16031014     0.35868556 ]
  }
)
% basis set specification
basis<GaussianBasisSet>: (
  name = "STO-3G"
  molecule = $:molecule
)
mpqc: (
  restart = no
  checkpoint = yes
  savestate = no
  % molecular coordinates for optimization
  coor<SymmMolecularCoor>: (
    molecule = $:molecule
    generator<IntCoorGen>: (
      molecule = $:molecule
    )
    followed<SumIntCoor>:(
      coor: [
        <StreSimpleCo>:(atoms = [1 5])
        <StreSimpleCo>:(atoms = [4 5])
      ]
      coef = [     1.0 -1.0]
    )
  )
  % method for computing the molecule's energy
  mole<CLHF>: (
    molecule = $:molecule
    basis = $:basis
    coor = $..:coor
    memory = 16000000
  )
  % optimizer object for the molecular geometry
  opt<EFCOpt>: (
    max_iterations = 1
    function = $..:mole
    transition_state = yes
    hessian = [ [ -0.1 ] ]
    mode_following = yes
    update<PowellUpdate>: ()
    convergence<MolEnergyConvergence>: (
      cartesian = yes
      energy = $..:..:mole
    )
  )
)