Run QChem under the control of Gaussian 16 with qchem_g16.
For example, you can use qchem_g16 to perform optimizations and transition
state searches using the algorithms in Gaussian but the quantum chemical
methods in QChem.
qchem_g16 is available as a statically-linked linux binary. Just download it
and put it somewhere on $PATH.
On other platforms, you can build it using Cargo and rustc,
git clone https://github.com/clavigne/qchem_g16
cd qchem_g16
cargo --build --releaseThe qchem_g16 binary is a well-behaved Gaussian external
program. It requires only one supplemental
argument --rem FILE, where FILE is a QChem input file containing a $rem
group. For example, the Gaussian input would look like this,
%NProcShared=4
# external="qchem_g16 --rem params.rem"
opt=(calcfc, noraman)
H2 optimization
0 1
C 1.38274 -0.22147 0.00555
C 0.50658 -1.30672 -0.00829
C -0.87138 -1.09065 -0.01412
C -1.37328 0.21076 -0.00468
C -0.49712 1.29590 0.00988
C 0.88087 1.07986 0.01426
H 2.45631 -0.38993 0.00964
H 0.89762 -2.32073 -0.01448
H -1.55394 -1.93613 -0.02612
H -2.44679 0.37914 -0.00858
H -0.88812 2.30994 0.01784
H 1.56346 1.92540 0.02438
and the QChem input (params.rem) like this,
$rem
method hf
basis 6-31g
$end
Provided that qchem and qchem_g16 are both on $PATH, running g16 on
this file will optimize benzene but with energy, gradient and Hessian
evaluations done by QChem.
Q-Chem will automatically use as many threads as %NProcShared.
- Run Q-Chem as an external program from Gaussian.
- Correct number of threads for Q-Chem.
- Provides energies, gradients and Hessians.
- Provides dipole moments and polarizability.
- Works with implicit solvation models.
qchem_g16 is free and unencumbered software released in the public
domain.
Made with ♥ using Rust 🦀 by me, Cyrille Lavigne.