def test_hessian_unit_regression(tmpdir):
"""
The modsem method was found to have a bug in the scaling code which caused all angles to be scaled by the same amount.
Here we try to reproduce some reference values for methanol which has a mix of scaled and non scaled angles.
"""
with tmpdir.as_cwd():
# load coords at the qm geometry
mol = Ligand.parse_file(get_data("methanol.json"))
mod_sem = ModSeminario()
mod_sem.run(molecule=mol)
# check the C-O bond
assert round(mol.BondForce[(0, 1)].length, ndigits=4) == 0.1413
# get in kcal/mol like the reference values
assert round(mol.BondForce[(0, 1)].k, 3) == 246439.036
# check a O-H bond
assert round(mol.BondForce[(1, 5)].length, 4) == 0.0957
assert round(mol.BondForce[(1, 5)].k, 2) == 513819.18
# check the C-O-H angle
assert round(mol.AngleForce[(0, 1, 5)].angle, 3) == 1.899
assert round(mol.AngleForce[(0, 1, 5)].k, 3) == 578.503
# check a scaled H-C-H angle
assert round(mol.AngleForce[(2, 0, 3)].angle, 3) == 1.894
assert round(mol.AngleForce[(2, 0, 3)].k, 3) == 357.05
def methanol():
return Ligand.parse_file(get_data("methanol.json"))
def coumarin():
return Ligand.parse_file(get_data("coumarin_hess_wbo.json"))
