Esempio n. 1
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}

water = Molecule(name='H2O', smiles='O')

# For the three different DFT functionals calculate the PES and plot the line
for dft_name, keywords in keywords_list.items():

    # Create arrays for OH distances and their energies
    rs = np.linspace(0.65, 2.0, num=15)
    energies = []

    # Calculate the energy array
    for r in rs:

        o_atom, h_atom = water.atoms[:2]
        curr_r = water.distance(0, 1)

        vector = (h_atom.coord - o_atom.coord) * (r / curr_r - 1)
        h_atom.translate(vector)

        # Set up and run the calculation
        calc = Calculation(name=f'H2O_scan_{r:.2f}',
                           molecule=water,
                           method=orca,
                           keywords=keywords)
        calc.run()

        # Get the potential energy from the calculation
        energy = calc.get_energy()
        energies.append(energy)
Esempio n. 2
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import numpy as np

# Initialise the electronic structure method (XTB)
xtb = XTB()

water = Molecule(name='H2O', smiles='O')
rs = np.linspace(0.65, 2.0, num=20)

# List of energies to be populated for the single point (unrelaxed)
# and constrained optimisations (relaxed) calculations
sp_energies, opt_energies = [], []

for r in rs:

    o_atom, h_atom = water.atoms[:2]
    curr_r = water.distance(0, 1)  # current O-H distance

    # Shift the hydrogen atom to the required distance
    # vector =  (h_atom.coord - o_atom.coord) / curr_r * (r - curr_r)
    vector = (h_atom.coord - o_atom.coord) * (r / curr_r - 1)
    h_atom.translate(vector)

    # Set up and run the single point energy evaluation
    sp = Calculation(name=f'H2O_scan_unrelaxed_{r:.2f}',
                     molecule=water,
                     method=xtb,
                     keywords=xtb.keywords.sp)
    sp.run()
    sp_energies.append(sp.get_energy())

    # Set up the constrained optimisation calculation where the distance
Esempio n. 3
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from autode import Molecule
from autode.input_output import xyz_file_to_atoms
from autode.conformers import conf_gen, Conformer
from autode.methods import XTB

# Initialise the complex from a .xyz file containing a square planar structure
vaskas = Molecule(name='vaskas', atoms=xyz_file_to_atoms('vaskas.xyz'))

# Set up some distance constraints where the keys are the atom indexes and
# the value the distance in Å. Fixing the Cl-P, Cl-P and Cl-C(=O) distances
# enforces a square planar geometry
distance_constraints = {(1, 2): vaskas.distance(1, 2),
                        (1, 3): vaskas.distance(1, 3),
                        (1, 4): vaskas.distance(1, 4)}

# Generate 5 conformers
for n in range(5):

    # Apply random displacements to each atom and minimise under a bonded +
    # repulsive forcefield including the distance constraints
    atoms = conf_gen.get_simanl_atoms(species=vaskas,
                                      dist_consts=distance_constraints,
                                      conf_n=n)

    # Generate a conformer from these atoms then optimise with XTB
    conformer = Conformer(name=f'vaskas_conf{n}', atoms=atoms)

    conformer.optimise(method=XTB())
    conformer.print_xyz_file()