示例#1
0
文件: thermo.py 项目: thackray/RMG-Py
    def estimateThermoViaGroupAdditivity(self, molecule):
        """
        Return the set of thermodynamic parameters corresponding to a given
        :class:`Molecule` object `molecule` by estimation using the group
        additivity values. If no group additivity values are loaded, a
        :class:`DatabaseError` is raised.
        """
        # For thermo estimation we need the atoms to already be sorted because we
        # iterate over them; if the order changes during the iteration then we
        # will probably not visit the right atoms, and so will get the thermo wrong
        molecule.sortVertices()

        # Create the ThermoData object
        thermoData = ThermoData(
            Tdata = ([300,400,500,600,800,1000,1500],"K"),
            Cpdata = ([0.0,0.0,0.0,0.0,0.0,0.0,0.0],"J/(mol*K)"),
            H298 = (0.0,"kJ/mol"),
            S298 = (0.0,"J/(mol*K)"),
        )

        if molecule.isRadical(): # radical species
            return self.estimateRadicalThermoViaHBI(molecule, self.estimateThermoViaGroupAdditivityForSaturatedStructWithoutSymmetryCorrection)

        else: # non-radical species
            thermoData = self.estimateThermoViaGroupAdditivityForSaturatedStructWithoutSymmetryCorrection(molecule)

        # Correct entropy for symmetry number
        molecule.calculateSymmetryNumber()
        thermoData.S298.value_si -= constants.R * math.log(molecule.symmetryNumber)

        return thermoData
示例#2
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文件: thermo.py 项目: olusade/RMG-Py
    def estimateThermoViaGroupAdditivity(self, molecule):
        """
        Return the set of thermodynamic parameters corresponding to a given
        :class:`Molecule` object `molecule` by estimation using the group
        additivity values. If no group additivity values are loaded, a
        :class:`DatabaseError` is raised.
        """
        # For thermo estimation we need the atoms to already be sorted because we
        # iterate over them; if the order changes during the iteration then we
        # will probably not visit the right atoms, and so will get the thermo wrong
        molecule.sortVertices()

        # Create the ThermoData object
        thermoData = ThermoData(
            Tdata=([300, 400, 500, 600, 800, 1000, 1500], "K"),
            Cpdata=([0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], "J/(mol*K)"),
            H298=(0.0, "kJ/mol"),
            S298=(0.0, "J/(mol*K)"),
        )

        if molecule.isRadical():  # radical species
            return self.estimateRadicalThermoViaHBI(
                molecule, self.
                estimateThermoViaGroupAdditivityForSaturatedStructWithoutSymmetryCorrection
            )

        else:  # non-radical species
            thermoData = self.estimateThermoViaGroupAdditivityForSaturatedStructWithoutSymmetryCorrection(
                molecule)

        # Correct entropy for symmetry number
        molecule.calculateSymmetryNumber()
        thermoData.S298.value_si -= constants.R * math.log(
            molecule.symmetryNumber)

        return thermoData
示例#3
0
文件: thermo.py 项目: thackray/RMG-Py
    def estimateRadicalThermoViaHBI(self, molecule, stableThermoEstimator ):
        """
        Estimate the thermodynamics of a radical by saturating it,
        applying the provided stableThermoEstimator method on the saturated species,
        then applying hydrogen bond increment corrections for the radical
        site(s) and correcting for the symmetry.
        
        The stableThermoEstimator should NOT have already corrected for the symmetry of the 
        stable saturated molecule, because we do not "uncorrect" it. 
        I.e. stableThermoEstimator should be a method that overestimates the entropy by R*ln(symmetry).
        """
        #TODO: check the validity of the above statement for QMThermo and databases.
        
        assert molecule.isRadical(), "Method only valid for radicals."
        
        # Make a copy of the structure so we don't change the original
        saturatedStruct = molecule.copy(deep=True)
        
        # Saturate structure by replacing all radicals with bonds to
        # hydrogen atoms
        added = {}
        for atom in saturatedStruct.atoms:
            for i in range(atom.radicalElectrons):
                H = Atom('H')
                bond = Bond(atom, H, 'S')
                saturatedStruct.addAtom(H)
                saturatedStruct.addBond(bond)
                if atom not in added:
                    added[atom] = []
                added[atom].append([H, bond])
                atom.decrementRadical()

        # Update the atom types of the saturated structure (not sure why
        # this is necessary, because saturating with H shouldn't be
        # changing atom types, but it doesn't hurt anything and is not
        # very expensive, so will do it anyway)
        saturatedStruct.updateConnectivityValues()
        saturatedStruct.sortVertices()
        saturatedStruct.updateAtomTypes()
        saturatedStruct.updateLonePairs()
        saturatedStruct.multiplicity = 1
        
        # Get thermo estimate for saturated form of structure
        try:
            thermoData = stableThermoEstimator(saturatedStruct)
        except AttributeError:
            # Probably looking for thermo in a library 
            saturatedSpec = Species(molecule=[saturatedStruct])
            thermoData = stableThermoEstimator(saturatedSpec)
            if thermoData:
                assert len(thermoData) == 3, "thermoData should be a tuple at this point: (thermoData, library, entry)"
                thermoData = thermoData[0]
        if thermoData is None:
            # logging.info("Thermo data of saturated {0} of molecule {1} is None.".format(saturatedStruct, molecule))
            return None
        assert thermoData is not None, "Thermo data of saturated {0} of molecule {1} is None!".format(saturatedStruct, molecule)
        
        # Correct entropy for symmetry number of radical structure
        molecule.calculateSymmetryNumber()
        thermoData.S298.value_si -= constants.R * math.log(molecule.symmetryNumber)
        
        # For each radical site, get radical correction
        # Only one radical site should be considered at a time; all others
        # should be saturated with hydrogen atoms
        for atom in added:
            # Remove the added hydrogen atoms and bond and restore the radical
            for H, bond in added[atom]:
                saturatedStruct.removeBond(bond)
                saturatedStruct.removeAtom(H)
                atom.incrementRadical()
            saturatedStruct.updateConnectivityValues()
            try:
                self.__addGroupThermoData(thermoData, self.groups['radical'], saturatedStruct, {'*':atom})
            except KeyError:
                logging.error("Couldn't find in radical thermo database:")
                logging.error(molecule)
                logging.error(molecule.toAdjacencyList())
                raise
            # Re-saturate
            for H, bond in added[atom]:
                saturatedStruct.addAtom(H)
                saturatedStruct.addBond(bond)
                atom.decrementRadical()
            # Subtract the enthalpy of the added hydrogens
            for H, bond in added[atom]:
                thermoData.H298.value_si -= 52.103 * 4184

        return thermoData
示例#4
0
    def estimateThermoViaGroupAdditivity(self, molecule):
        """
        Return the set of thermodynamic parameters corresponding to a given
        :class:`Molecule` object `molecule` by estimation using the group
        additivity values. If no group additivity values are loaded, a
        :class:`DatabaseError` is raised.
        """
        # For thermo estimation we need the atoms to already be sorted because we
        # iterate over them; if the order changes during the iteration then we
        # will probably not visit the right atoms, and so will get the thermo wrong
        molecule.sortVertices()

        # Create the ThermoData object
        thermoData = ThermoData(
            Tdata = ([300,400,500,600,800,1000,1500],"K"),
            Cpdata = ([0.0,0.0,0.0,0.0,0.0,0.0,0.0],"J/(mol*K)"),
            H298 = (0.0,"kJ/mol"),
            S298 = (0.0,"J/(mol*K)"),
        )

        if molecule.getRadicalCount() > 0: # radical species
            return self.estimateRadicalThermoViaHBI(molecule, self.estimateThermoViaGroupAdditivity )

        else: # non-radical species
            cyclic = molecule.isCyclic()
            # Generate estimate of thermodynamics
            for atom in molecule.atoms:
                # Iterate over heavy (non-hydrogen) atoms
                if atom.isNonHydrogen():
                    # Get initial thermo estimate from main group database
                    try:
                        self.__addGroupThermoData(thermoData, self.groups['group'], molecule, {'*':atom})
                    except KeyError:
                        logging.error("Couldn't find in main thermo database:")
                        logging.error(molecule)
                        logging.error(molecule.toAdjacencyList())
                        raise
                    # Correct for gauche and 1,5- interactions
                    if not cyclic:
                        try:
                            self.__addGroupThermoData(thermoData, self.groups['gauche'], molecule, {'*':atom})
                        except KeyError: pass
                    try:
                        self.__addGroupThermoData(thermoData, self.groups['int15'], molecule, {'*':atom})
                    except KeyError: pass
                    try:
                        self.__addGroupThermoData(thermoData, self.groups['other'], molecule, {'*':atom})
                    except KeyError: pass

            # Do ring corrections separately because we only want to match
            # each ring one time
            
            if cyclic:                
                if molecule.getAllPolycyclicVertices():
                    # If the molecule has fused ring atoms, this implies that we are dealing
                    # with a polycyclic ring system, for which separate ring strain corrections may not
                    # be adequate.  Therefore, we search the polycyclic thermo group corrections
                    # instead of adding single ring strain corrections within the molecule.
                    # For now, assume only one  polycyclic RSC can be found per molecule
                    try:
                        self.__addGroupThermoData(thermoData, self.groups['polycyclic'], molecule, {})
                    except:
                        logging.error("Couldn't find in polycyclic ring database:")
                        logging.error(molecule)
                        logging.error(molecule.toAdjacencyList())
                        raise
                else:
                    rings = molecule.getSmallestSetOfSmallestRings()
                    for ring in rings:
                        # Make a temporary structure containing only the atoms in the ring
                        # NB. if any of the ring corrections depend on ligands not in the ring, they will not be found!
                        try:
                            self.__addGroupThermoData(thermoData, self.groups['ring'], molecule, {})
                        except KeyError:
                            logging.error("Couldn't find in ring database:")
                            logging.error(ring)
                            logging.error(ring.toAdjacencyList())
                            raise
                            
                
        # Correct entropy for symmetry number
        molecule.calculateSymmetryNumber()
        thermoData.S298.value_si -= constants.R * math.log(molecule.symmetryNumber)

        return thermoData
示例#5
0
    def estimateRadicalThermoViaHBI(self, molecule, stableThermoEstimator ):
        """
        Estimate the thermodynamics of a radical by saturating it,
        applying the provided stableThermoEstimator method on the saturated species,
        then applying hydrogen bond increment corrections for the radical
        site(s) and correcting for the symmetry.
        """
        assert molecule.getRadicalCount() > 0, "Method only valid for radicals."
        
        # Make a copy of the structure so we don't change the original
        saturatedStruct = molecule.copy(deep=True)
        
        # Saturate structure by replacing all radicals with bonds to
        # hydrogen atoms
        added = {}
        for atom in saturatedStruct.atoms:
            for i in range(atom.radicalElectrons):
                H = Atom('H')
                bond = Bond(atom, H, 'S')
                saturatedStruct.addAtom(H)
                saturatedStruct.addBond(bond)
                if atom not in added:
                    added[atom] = []
                added[atom].append([H, bond])
                atom.decrementRadical()
        
        # Update the atom types of the saturated structure (not sure why
        # this is necessary, because saturating with H shouldn't be
        # changing atom types, but it doesn't hurt anything and is not
        # very expensive, so will do it anyway)
        saturatedStruct.updateConnectivityValues()
        saturatedStruct.sortVertices()
        saturatedStruct.updateAtomTypes()
        
        # Get thermo estimate for saturated form of structure
        thermoData = stableThermoEstimator(saturatedStruct)
        if thermoData is None:
            logging.info("Thermo data of saturated {0} of molecule {1} is None.".format(saturatedStruct, molecule))
            return None
        assert thermoData is not None, "Thermo data of saturated {0} of molecule {1} is None!".format(saturatedStruct, molecule)
        
        # Undo symmetry number correction for saturated structure
        saturatedStruct.calculateSymmetryNumber()
        thermoData.S298.value_si += constants.R * math.log(saturatedStruct.symmetryNumber)
        # Correct entropy for symmetry number of radical structure
        molecule.calculateSymmetryNumber()
        thermoData.S298.value_si -= constants.R * math.log(molecule.symmetryNumber)
        
        # For each radical site, get radical correction
        # Only one radical site should be considered at a time; all others
        # should be saturated with hydrogen atoms
        for atom in added:
            # Remove the added hydrogen atoms and bond and restore the radical
            for H, bond in added[atom]:
                saturatedStruct.removeBond(bond)
                saturatedStruct.removeAtom(H)
                atom.incrementRadical()
            saturatedStruct.updateConnectivityValues()
            try:
                self.__addGroupThermoData(thermoData, self.groups['radical'], saturatedStruct, {'*':atom})
            except KeyError:
                logging.error("Couldn't find in radical thermo database:")
                logging.error(molecule)
                logging.error(molecule.toAdjacencyList())
                raise
            # Re-saturate
            for H, bond in added[atom]:
                saturatedStruct.addAtom(H)
                saturatedStruct.addBond(bond)
                atom.decrementRadical()
            # Subtract the enthalpy of the added hydrogens
            for H, bond in added[atom]:
                thermoData.H298.value_si -= 52.103 * 4184

        return thermoData