def to_openmm_Modeller(item,
                       atom_indices='all',
                       coordinates=None,
                       box=None,
                       check=True):

    if check:

        digest_item(item, 'openmm.Topology')
        atom_indices = digest_atom_indices(atom_indices)
        coordinates = digest_coordinates(coordinates)
        box = digest_box(box)

    from . import extract
    from molsysmt import puw
    from openmm.app import Modeller

    tmp_item = extract(item,
                       atom_indices=atom_indices,
                       copy_if_all=False,
                       check=False)
    positions = puw.convert(coordinates[0], 'nm', to_form='openmm.unit')
    tmp_item = Modeller(tmp_item, positions)

    return tmp_item
Exemple #2
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def to_mdtraj_Trajectory(item, atom_indices='all', check=True):

    if check:

        try:
            is_pdbfixer_PDBFixer(item)
        except:
            raise WrongFormError('pdbfixer.PDBFixer')

        try:
            atom_indices = digest_atom_indices(atom_indices)
        except:
            raise WrongAtomIndicesError()

    try:
        from mdtraj.core.trajectory import Trajectory as mdtraj_Trajectory
    except:
        raise LibraryNotFoundError('MDTraj')

    from molsysmt import puw
    from . import to_mdtraj_Topology
    from . import get_coordinates_from_atom

    tmp_item = to_mdtraj_Topology(item, atom_indices=atom_indices, check=False)
    coordinates = get_coordinates_from_atom(tmp_item,
                                            indices=atom_indices,
                                            check=False)
    coordinates = puw.convert(coordinates,
                              to_units='nanometer',
                              to_form='openmm.unit')
    tmp_item = mdtraj_Trajectory(coordinates, tmp_item)

    return tmp_item
def to_openmm_Modeller(item, atom_indices='all', check=True):

    if check:

        try:
            is_pdbfixer_PDBFixer(item)
        except:
            raise WrongFormError('pdbfixer.PDBFixer')

        try:
            atom_indices = digest_atom_indices(atom_indices)
        except:
            raise WrongAtomIndicesError()

        try:
            structure_indices = digest_structure_indices(structure_indices)
        except:
            raise WrongStructureIndicesError()

    from molsysmt import puw
    from . import to_openmm_Topology

    tmp_item = to_openmm_Topology(item, atom_indices=atom_indices, check=False)
    coordinates = get_coordinates_from_atom(tmp_item,
                                            indices=atom_indices,
                                            check=False)
    coordinates = puw.convert(coordinates,
                              to_units='nanometer',
                              to_form='openmm.unit')
    tmp_item = openmm_Modeller(tmp_item, coordinates)

    return tmp_item
Exemple #4
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def to_openmm_Simulation(item,
                         molecular_system=None,
                         atom_indices='all',
                         structure_indices='all'):

    from molsysmt.basic import convert, get
    from openmm.app import Simulation

    topology = convert(molecular_system,
                       to_form='openmm.Topology',
                       selection=atom_indices)
    positions = get(molecular_system,
                    target='atom',
                    selection=atom_indices,
                    structure_indices=structure_indices,
                    coordinates=True)
    positions = puw.convert(positions[0], to_unit='nm', to_form='openmm.unit')
    simulation = convert(molecular_system, to_form='molsysmt.Simulation')

    integrator = simulation.to_openmm_Integrator()
    platform = simulation.to_openmm_Platform()

    properties = simulation.get_openmm_Simulation_parameters()

    tmp_item = Simulation(topology, item, integrator, platform, properties)
    tmp_item.context.setPositions(positions)
    if simulation.initial_velocities_to_temperature:
        temperature = puw.convert(simulation.temperature,
                                  to_unit='K',
                                  to_form='openmm.unit')
        tmp_item.context.setVelocitiesToTemperature(temperature)

    if molecular_system is not None:
        tmp_molecular_system = molecular_system.combine_with_items(
            tmp_item,
            atom_indices=atom_indices,
            structure_indices=structure_indices)
    else:
        tmp_molecular_system = None

    return tmp_item, tmp_molecular_system
Exemple #5
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    def to_openmm_Integrator(self):

        from openmm import LangevinIntegrator

        temperature = puw.convert(self.temperature,
                                  to_unit='K',
                                  to_form='openmm.unit')
        collisions_rate = puw.convert(self.collisions_rate,
                                      to_unit='1/ps',
                                      to_form='openmm.unit')
        integration_timestep = puw.convert(self.integration_timestep,
                                           to_unit='fs',
                                           to_form='openmm.unit')

        if self.integrator == 'Langevin':
            integrator = LangevinIntegrator(temperature, collisions_rate,
                                            integration_timestep)
            if self.constraint_tolerance is not None:
                integrator.setConstraintTolerance(self.constraint_tolerance)
        else:
            raise NotImplementedError()

        return integrator
Exemple #6
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def unwrap(molecular_system, selection='all', structure_indices='all',
        syntaxis='MolSysMT', engine='MolSysMT', in_place=False):

    engine = digest_engine(engine)
    structure_indices = digest_structure_indices(structure_indices)

    if engine=='MolSysMT':

        from molsysmt.basic import select, get, set, extract

        coordinates= get(molecular_system, target='atom', selection=selection, coordinates=True)
        n_structures = coordinates.shape[0]
        n_atoms = coordinates.shape[1]
        box, box_shape = get(molecular_system, target='system', structure_indices=structure_indices, box=True, box_shape=True)

        orthogonal = 0
        if box_shape is None:
            raise ValueError("The system has no PBC box. The input argument 'pbc' can not be True.")
        elif box_shape == 'cubic':
            orthogonal =1

        length_units = puw.get_unit(coordinates)
        box = puw.convert(box, to_unit=length_units)

        box = np.asfortranarray(puw.get_value(box), dtype='float64')
        coordinates = np.asfortranarray(puw.get_value(coordinates), dtype='float64')

        libbox.unwrap(coordinates, box, orthogonal, n_atoms, n_structures)

        coordinates=np.ascontiguousarray(coordinates)*length_units

    else:

        raise NotImpementedEngineError()

    if in_place:

        set(molecular_system, target='atom', selection=selection, structure_indices=structure_indices,
                syntaxis=syntaxis, coordinates=coordinates)

        pass

    else:

        tmp_molecular_system = extract(molecular_system, selection=selection, structure_indices=structure_indices, syntaxis=syntaxis)
        set(tmp_molecular_system, target='atom', selection='all', structure_indices='all', syntaxis='MolSysMT', coordinates=coordinates)

        return tmp_molecular_system
Exemple #7
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def set_coordinates_to_atom(item,
                            indices='all',
                            structure_indices='all',
                            value=None):

    length_unit = puw.get_unit(item['coordinates'])
    value = puw.convert(value, to_unit=length_unit)

    if indices is 'all':
        if structure_indices is 'all':
            item['coordinates'] = value
        else:
            item['coordinates'][structure_indices, :, :] = value
    else:
        if structure_indices is 'all':
            item['coordinates'][:, indices, :] = value
        else:
            item['coordinates'][np.ix_(indices, structure_indices)] = value

    pass
Exemple #8
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def to_string_pdb_text(item,
                       atom_indices='all',
                       coordinates=None,
                       box=None,
                       check=True):

    if check:

        digest_item(item, 'openmm.Topology')
        atom_indices = digest_atom_indices(atom_indices)
        coordinates = digest_coordinates(coordinates)
        box = digest_box(box)

    from io import StringIO
    from openmm.app import PDBFile
    from molsysmt import __version__ as msm_version
    from openmm import Platform  # the openmm version is taken from this module (see: openmm/app/pdbfile.py)
    from molsysmt import puw

    n_structures = coordinates.shape[0]
    if n_structures > 1:
        import warnings
        warnings.warn(
            "Openmm.Topology/to_string_pdb_text got more than a single structure. Only the 0-th is taken."
        )

    tmp_io = StringIO()
    coordinates = puw.convert(coordinates[0], 'nm', to_form='openmm.unit')
    PDBFile.writeFile(item, coordinates, tmp_io, keepIds=True)
    filedata = tmp_io.getvalue()
    openmm_version = Platform.getOpenMMVersion()
    filedata = filedata.replace(
        'WITH OPENMM ' + openmm_version,
        'WITH OPENMM ' + openmm_version + ' BY MOLSYSMT ' + msm_version)
    tmp_io.close()
    del (tmp_io)

    tmp_item = filedata

    return tmp_item
Exemple #9
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def set_box_to_system(item, structure_indices='all', value=None, check=True):

    if check:

        _digest_item(item, 'openmm.Topology')
        structure_indices = _digest_structure_indices(structure_indices)
        box = _digest_box(value)

    box = _puw.convert(value, to_unit='nanometers', to_form='openmm.unit')

    n_structures = box.shape[0]

    if n_structures == 1:

        item.setPeriodicBoxVectors(box[0])

    else:

        raise ValueError(
            "The box to set in to a openmm.Topology has more than a frame")

    pass
Exemple #10
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def to_openmm_Modeller(item, atom_indices='all', structure_indices='all', check=True):

    if check:

        digest_item(item, 'molsysmt.MolSys')
        atom_indices = digest_atom_indices(atom_indices)
        structure_indices = digest_structure_indices(structure_indices)

    try:
        from openmm.app import Modeller
    except:
        raise LibraryNotFound(openmm)

    from . import to_openmm_Topology
    from . import get_coordinates_from_atom
    from molsysmt import puw

    tmp_topology = to_openmm_Topology(item, atom_indices=atom_indices, structure_indices=structure_indices, check=False)
    tmp_positions = get_coordinates_from_atom(item, indices=atom_indices, structure_indices=structure_indices, check=False)
    tmp_positions = puw.convert(tmp_positions, to_form='openmm.unit')

    tmp_item = Modeller(tmp_topology, tmp_positions[0])

    return tmp_item
Exemple #11
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def wrap_to_pbc(molecular_system,
                selection='all',
                structure_indices='all',
                center='[0,0,0] nanometers',
                center_of_selection=None,
                weights_for_center=None,
                recenter=True,
                keep_covalent_bonds=False,
                syntaxis='MolSysMT',
                engine='MolSysMT',
                in_place=False):

    engine = digest_engine(engine)
    structure_indices = digest_structure_indices(structure_indices)

    if engine == 'MolSysMT':

        from molsysmt.basic import select, get, set, extract, copy

        atom_indices = select(molecular_system,
                              selection=selection,
                              syntaxis=syntaxis)

        coordinates = get(molecular_system,
                          target='atom',
                          indices=atom_indices,
                          coordinates=True)
        length_units = puw.get_unit(coordinates)
        n_structures = coordinates.shape[0]
        n_atoms = coordinates.shape[1]
        box, box_shape = get(molecular_system,
                             target='system',
                             structure_indices=structure_indices,
                             box=True,
                             box_shape=True)
        box = puw.convert(box, to_unit=length_units)

        orthogonal = 0
        if box_shape is None:
            raise ValueError(
                "The system has no PBC box. The input argument 'pbc' can not be True."
            )
        elif box_shape == 'cubic':
            orthogonal = 1

        if center_of_selection is not None:

            from molsysmt.structure import get_center
            center = get_center(molecular_system,
                                selection=center_of_selection,
                                weights=weights_for_center,
                                structure_indices=structure_indices,
                                syntaxis=syntaxis,
                                engine='MolSysMT')

            center = puw.convert(center, to_unit=length_units)
            center = puw.get_value(center)

        else:

            center = puw.quantity(center)
            center = puw.convert(center, to_unit=length_units)
            center = puw.get_value(center)

            center_shape = np.shape(center)
            if len(center_shape) == 1 and center_shape[-1] == 3:
                center = np.tile(center, [n_structures, 1, 1])
            elif len(center_shape) == 2 and center_shape[
                    -1] == 3 and center_shape[0] == n_structures:
                center = np.expand_dims(center, axis=1)
            elif len(center_shape
                     ) == 2 and center_shape[-1] == 3 and center_shape[0] == 1:
                center = np.tile(center[0], [n_structures, 1, 1])
            elif len(center_shape
                     ) == 3 and center_shape[-1] == 3 and center_shape[
                         0] == n_structures and center_shape[1] == 1:
                center = np.array(center)
            else:
                raise ValueError('center needs the right shape')

        box = np.asfortranarray(puw.get_value(box), dtype='float64')
        coordinates = np.asfortranarray(puw.get_value(coordinates),
                                        dtype='float64')
        center = np.asfortranarray(center, dtype='float64')

        libbox.wrap_pbc(coordinates, center, box, orthogonal, n_atoms,
                        n_structures)

        if recenter:
            translation = np.tile(-center, (n_atoms, 1))
            coordinates += translation

        coordinates = np.ascontiguousarray(coordinates) * length_units

    else:

        raise NotImpementedEngineError()

    if in_place:

        set(molecular_system,
            target='atom',
            indices=atom_indices,
            structure_indices=structure_indices,
            syntaxis=syntaxis,
            coordinates=coordinates)

        pass

    else:

        tmp_molecular_system = copy(molecular_system)
        set(tmp_molecular_system,
            target='atom',
            indices=atom_indices,
            structure_indices=structure_indices,
            syntaxis=syntaxis,
            coordinates=coordinates)

        return tmp_molecular_system
Exemple #12
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def solvate(molecular_system,
            box_geometry="truncated octahedral",
            clearance='14.0 angstroms',
            anion='Cl-',
            num_anions="neutralize",
            cation='Na+',
            num_cations="neutralize",
            ionic_strength='0.0 molar',
            engine="LEaP",
            to_form=None,
            logfile=False,
            verbose=False):
    """solvate(item, geometry=None, water=None, engine=None)
    Methods and wrappers to create and solvate boxes
    Parameters
    ----------
    anion: 'Cl-', 'Br-', 'F-', and 'I-'
    num_anions: number of cations to add. integer or "neutralize"
    cation: "NA"  'Cs+', 'K+', 'Li+', 'Na+', and 'Rb+'
    num_cations: number of cations to add. integer or "neutralize"
    box_geometry: "cubic", "truncated_octahedral" or "rhombic_dodecahedron" (Default: "truncated_octahedral")
    Returns
    -------
    item : bla bla
        bla bla
    Examples
    --------
    See Also
    --------
    Notes
    -----
    """

    from molsysmt.basic import get_form, convert

    engine = digest_engine(engine)
    to_form = digest_to_form(to_form)
    if to_form is None:
        to_form = get_form(molecular_system)

    if engine == "OpenMM":

        from openmm import Vec3

        clearance = puw.convert(clearance, to_form='openmm.unit')
        ionic_strength = puw.convert(ionic_strength, to_form='openmm.unit')

        modeller = convert(molecular_system, to_form='openmm.Modeller')
        molecular_mechanics = convert(molecular_system,
                                      to_form='molsysmt.MolecularMechanics')
        parameters = molecular_mechanics.get_openmm_System_parameters()
        forcefield = molecular_mechanics.to_openmm_ForceField()

        solvent_model = None
        if molecular_mechanics.water_model == 'SPC':
            solvent_model = 'tip3p'
        elif molecular_mechanics.water_model in [
                'TIP3P', 'TIP3PFB', 'SPCE', 'TIP4PEW', 'TIP4PFB', 'TIP5P'
        ]:
            solvent_model = molecular_mechanics.water_model.lower()
        else:
            raise NotImplementedError()

        if box_geometry == "truncated octahedral":

            max_size = max(
                max((pos[i] for pos in modeller.positions)) -
                min((pos[i] for pos in modeller.positions)) for i in range(3))
            vectors = Vec3(1.0, 0,
                           0), Vec3(1.0 / 3.0, 2.0 * np.sqrt(2.0) / 3.0,
                                    0.0), Vec3(-1.0 / 3.0,
                                               np.sqrt(2.0) / 3.0,
                                               np.sqrt(6.0) / 3.0)
            box_vectors = [(max_size + clearance) * v for v in vectors]

            modeller.addSolvent(forcefield,
                                model=solvent_model,
                                boxVectors=box_vectors,
                                ionicStrength=ionic_strength,
                                positiveIon=cation,
                                negativeIon=anion)

        elif box_geometry == "rhombic dodecahedral":

            max_size = max(
                max((pos[i] for pos in modeller.positions)) -
                min((pos[i] for pos in modeller.positions)) for i in range(3))
            vectors = Vec3(1.0, 0.0,
                           0.0), Vec3(0.0, 1.0,
                                      0.0), Vec3(0.5, 0.5,
                                                 np.sqrt(2) / 2)
            box_vectors = [(max_size + clearance) * v for v in vectors]

            modeller.addSolvent(forcefield,
                                model=solvent_model,
                                boxVectors=box_vectors,
                                ionicStrength=ionic_strength,
                                positiveIon=cation,
                                negativeIon=anion)

        else:

            modeller.addSolvent(forcefield,
                                model=solvent_model,
                                padding=clearance,
                                ionicStrength=ionic_strength,
                                positiveIon=cation,
                                negativeIon=anion)

        tmp_item = convert(modeller, to_form=to_form)

        del (modeller)

        return tmp_item

    elif engine == "PDBFixer":

        from openmm import Vec3

        clearance = puw.convert(clearance, to_form='openmm.unit')
        ionic_strength = puw.convert(ionic_strength, to_form='openmm.unit')

        pdbfixer = convert(molecular_system, to_form='pdbfixer.PDBFixer')
        max_size = max(
            max((pos[i] for pos in pdbfixer.positions)) -
            min((pos[i] for pos in pdbfixer.positions)) for i in range(3))

        box_size = None
        box_vectors = None

        if box_geometry == "truncated octahedral":

            vectors = Vec3(1.0, 0,
                           0), Vec3(1.0 / 3.0, 2.0 * np.sqrt(2.0) / 3.0,
                                    0.0), Vec3(-1.0 / 3.0,
                                               np.sqrt(2.0) / 3.0,
                                               np.sqrt(6.0) / 3.0)

        elif box_geometry == "rhombic dodecahedral":

            vectors = Vec3(1.0, 0.0,
                           0.0), Vec3(0.0, 1.0,
                                      0.0), Vec3(0.5, 0.5,
                                                 np.sqrt(2) / 2)

        elif box_geometry == "cubic":

            vectors = Vec3(1.0, 0.0, 0.0), Vec3(0.0, 1.0,
                                                0.0), Vec3(0.0, 0.0, 1.0)

        box_vectors = [(max_size + clearance) * v for v in vectors]

        pdbfixer.addSolvent(boxVectors=box_vectors,
                            ionicStrength=ionic_strength,
                            positiveIon=cation,
                            negativeIon=anion)

        tmp_item = convert(pdbfixer, to_form=to_form)

        del (pdbfixer)

        return tmp_item

    elif engine == "LEaP":

        from molsysmt.thirds.tleap import TLeap
        from molsysmt._private.files_and_directories import temp_directory, temp_filename
        from molsysmt.tools.file_pdb import replace_HETATM_by_ATOM_in_terminal_cappings
        from shutil import rmtree, copyfile
        from os import getcwd, chdir
        from molsysmt.basic import set as _set, select
        from molsysmt.build import has_hydrogens, remove_hydrogens

        if has_hydrogens(molecular_system):
            raise ValueError(
                "A molecular system without hydrogen atoms is needed.")
            #molecular_system = remove_hydrogens(molecular_system)
            #if verbose:
            #    print("All Hydrogen atoms were removed to be added by LEaP\n\n")

        indices_NME_C = select(
            molecular_system,
            target='atom',
            selection='group_name=="NME" and atom_name=="C"')
        with_NME_C = (len(indices_NME_C) > 0)

        if with_NME_C:
            _set(molecular_system,
                 target='atom',
                 selection='group_name=="NME" and atom_name=="C"',
                 atom_name='CH3')

        current_directory = getcwd()
        working_directory = temp_directory()
        pdbfile_in = temp_filename(dir=working_directory, extension='pdb')
        _ = convert(molecular_system, to_form=pdbfile_in)
        #replace_HETATM_from_capping_atoms(pdbfile_in)

        tmp_prmtop = temp_filename(dir=working_directory, extension='prmtop')
        tmp_inpcrd = tmp_prmtop.replace('prmtop', 'inpcrd')
        tmp_logfile = tmp_prmtop.replace('prmtop', 'leap.log')

        molecular_mechanics = convert(molecular_system,
                                      to_form='molsysmt.MolecularMechanics')
        parameters = molecular_mechanics.get_leap_parameters()
        forcefield = parameters['forcefield']
        water = parameters['water_model']

        solvent_model = None
        if water == 'SPC':
            solvent_model = 'SPCBOX'
        elif water == 'TIP3P':
            solvent_model = 'TIP3PBOX'
        elif water == 'TIP4P':
            solvent_model = 'TIP4PBOX'

        if verbose:
            print('Working directory:', working_directory)

        tleap = TLeap()
        tleap.load_parameters(*forcefield)
        tleap.load_unit('MolecularSystem', pdbfile_in)
        tleap.check_unit('MolecularSystem')
        tleap.get_total_charge('MolecularSystem')
        tleap.solvate('MolecularSystem',
                      solvent_model,
                      clearance,
                      box_geometry=box_geometry)

        if num_anions != 0:
            if num_anions == 'neutralize':
                num_anions = 0
            tleap.add_ions('MolecularSystem',
                           anion,
                           num_ions=num_anions,
                           replace_solvent=True)

        if num_cations != 0:
            if num_cations == 'neutralize':
                num_cations = 0
            tleap.add_ions('MolecularSystem',
                           cation,
                           num_ions=num_cations,
                           replace_solvent=True)

        tleap.save_unit('MolecularSystem', tmp_prmtop)
        errors = tleap.run(working_directory=working_directory,
                           verbose=verbose)

        del (tleap)

        if logfile:
            copyfile(tmp_logfile, current_directory + '/build_peptide.log')

        tmp_item = convert([tmp_prmtop, tmp_inpcrd], to_form=to_form)

        if with_NME_C:
            _set(tmp_item,
                 target='atom',
                 selection='group_name=="NME" and atom_name=="CH3"',
                 atom_name='C')

        rmtree(working_directory)

        return tmp_item

    else:

        raise NotImplementedError
    def get_openmm_System_parameters(self):

        from openmm import app

        parameters = {}

        if self.non_bonded_method == 'no_cutoff':
            parameters['nonbondedMethod'] = app.NoCutoff
        elif self.non_bonded_method == 'cutoff_non_periodic':
            parameters['nonbondedMethod'] = app.CutoffNonPeriodic
        elif self.non_bonded_method == 'cutoff_periodic':
            parameters['nonbondedMethod'] = app.CutoffPeriodic
        elif self.non_bonded_method == 'Ewald':
            parameters['nonbondedMethod'] = app.Ewald
        elif self.non_bonded_method == 'PME':
            parameters['nonbondedMethod'] = app.PME
        elif self.non_bonded_method == 'LJPME':
            parameters['nonbondedMethod'] = app.LJPME
        else:
            raise NotImplementedError()

        if self.non_bonded_cutoff is not None:
            parameters['nonbondedCutoff'] = puw.convert(self.non_bonded_cutoff,
                                                        to_form='openmm.unit',
                                                        to_unit='nm')

        if self.switch_distance is not None:
            parameters['switchDistance'] = puw.convert(self.switch_distance,
                                                       to_form='openmm.unit',
                                                       to_unit='nm')

        if self.constraints is not None:
            if self.constraints == 'h_bonds':
                parameters['constraints'] = app.HBonds
            elif self.constraints == 'all_bonds':
                parameters['constraints'] = app.HBonds
            elif self.constraints == 'h_angles':
                parameters['constraints'] = app.HAngles
            else:
                raise NotImplementedError()
        else:
            parameters['constraints'] = None

        parameters['hydrogenMass'] = self.hydrogen_mass
        parameters['rigidWater'] = self.rigid_water
        #parameters['removeCMMotion']=self.remove_cm_motion
        parameters['residueTemplates'] = self.residue_templates
        parameters['ignoreExternalBonds'] = self.ignore_external_bonds
        parameters['flexibleConstraints'] = self.flexible_constraints

        if self.implicit_solvent is not None:

            if self.implicit_solvent == 'HCT':
                parameters['implicitSolvent'] = app.HCT
            elif self.implicit_solvent == 'OBC1':
                parameters['implicitSolvent'] = app.OBC1
            elif self.implicit_solvent == 'OBC2':
                parameters['implicitSolvent'] = app.OBC2
            elif self.implicit_solvent == 'GBn':
                parameters['implicitSolvent'] = app.GBn
            elif self.implicit_solvent == 'GBn2':
                parameters['implicitSolvent'] = app.GBn2
            else:
                raise NotImplementedError

            parameters['implicitSolventSaltConc'] = puw.convert(
                self.implicit_solvent_salt_cont,
                to_unit='mole/liter',
                to_form='openmm.unit')
            parameters['implicitSolventKappa'] = puw.convert(
                self.implicit_solvent_salt_kappa,
                to_unit='1/nm',
                to_form='openmm.unit')
            parameters['soluteDielectric'] = self.solute_dielectric
            parameters['solventDielectric'] = self.solvent_dielectric

        else:
            parameters['implicitSolvent'] = None

        #parameters['useDispersionCorrection']=self.use_dispersion_correction
        #parameters['ewaldErrorTolerance']=self.ewald_error_tolerance

        return parameters