Esempio n. 1
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    def calculate_energies_and_modes(self):
        if hasattr(self, 'im_r'):
            return

        ResonantRaman.calculate_energies_and_modes(self)

        # single transitions and their occupation
        om_Q = self.om_Q[self.skip:]
        om_v = om_Q
        ndof = len(om_Q)
        n_vQ = np.eye(ndof, dtype=int)

        l_Q = range(ndof)
        ind_v = list(combinations_with_replacement(l_Q, 1))

        if self.combinations > 1:
            if not self.combinations == 2:
                raise NotImplementedError

            for c in range(2, self.combinations + 1):
                ind_v += list(combinations_with_replacement(l_Q, c))

            nv = len(ind_v)
            n_vQ = np.zeros((nv, ndof), dtype=int)
            om_v = np.zeros((nv), dtype=float)
            for j, wt in enumerate(ind_v):
                for i in wt:
                    n_vQ[j, i] += 1
            om_v = n_vQ.dot(om_Q)

        self.ind_v = ind_v
        self.om_v = om_v
        self.n_vQ = n_vQ  # how many of each
        self.d_vQ = np.where(n_vQ > 0, 1, 0)  # do we have them ?
Esempio n. 2
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    def read(self, method='standard', direction='central'):
        ResonantRaman.read(self, method, direction)

        # single transitions and their occupation
        om_Q = self.om_Q[self.skip:]
        om_v = om_Q
        ndof = len(om_Q)
        n_vQ = np.eye(ndof, dtype=int)

        l_Q = range(ndof)
        ind_v = list(combinations_with_replacement(l_Q, 1))

        if self.combinations > 1:
            if not self.combinations == 2:
                raise NotImplementedError

            for c in range(2, self.combinations + 1):
                ind_v += list(combinations_with_replacement(l_Q, c))

            nv = len(ind_v)
            n_vQ = np.zeros((nv, ndof), dtype=int)
            om_v = np.zeros((nv), dtype=float)
            for j, wt in enumerate(ind_v):
                for i in wt:
                    n_vQ[j, i] += 1
            om_v = n_vQ.dot(om_Q)

        self.ind_v = ind_v
        self.om_v = om_v
        self.n_vQ = n_vQ  # how many of each
        self.d_vQ = np.where(n_vQ > 0, 1, 0)  # do we have them ?
Esempio n. 3
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    def __init__(self, *args, **kwargs):
        """
        Parameters
        ----------
        all from ResonantRaman.__init__
        combinations: int
            Combinations to consider for multiple excitations.
            Default is 1, possible 2
        skip: int
            Number of first transitions to exclude. Default 0,
            recommended: 5 for linear molecules, 6 for other molecules
        nm: int
            Number of intermediate m levels to consider, default 20
        """
        self.combinations = kwargs.pop('combinations', 1)
        self.skip = kwargs.pop('skip', 0)
        self.nm = kwargs.pop('nm', 20)
        approximation = kwargs.pop('approximation', 'Albrecht')

        ResonantRaman.__init__(self, *args, **kwargs)

        self.set_approximation(approximation)
Esempio n. 4
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 def __init__(self, *args, **kwargs):
     self.set_approximation(kwargs.pop('approximation', 'Profeta'))
     self.nonresonant = kwargs.pop('nonresonant', True)
     ResonantRaman.__init__(self, *args, **kwargs)
Esempio n. 5
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 def __init__(self, *args, **kwargs):
     self._approx = 'PlaczekAlpha'
     ResonantRaman.__init__(self, *args, **kwargs)
Esempio n. 6
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from ase.vibrations.resonant_raman import ResonantRaman

from gpaw.cluster import Cluster
from gpaw import GPAW, FermiDirac
from gpaw.lrtddft import LrTDDFT

h = 0.25
atoms = Cluster('relaxed.traj')
atoms.minimal_box(3.5, h=h)

# relax the molecule
calc = GPAW(h=h,
            occupations=FermiDirac(width=0.1),
            eigensolver='cg',
            symmetry={'point_group': False},
            nbands=10,
            convergence={
                'eigenstates': 1.e-5,
                'bands': 4
            })
atoms.calc = calc

# use only the 4 converged states for linear response calculation
rr = ResonantRaman(atoms, LrTDDFT, exkwargs={'jend': 3})
rr.run()
Esempio n. 7
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c = 5.0
H2 = Atoms([
    Atom('H', (a / 2, a / 2, (c - R) / 2)),
    Atom('H', (a / 2, a / 2, (c + R) / 2))
],
           cell=(a, a, c))

calc = GPAW(xc=xc, nbands=3, spinpol=False, eigensolver='rmm-diis', txt=txt)
H2.set_calculator(calc)
H2.get_potential_energy()

gsname = exname = 'rraman'
rr = ResonantRaman(H2,
                   KSSingles,
                   gsname=gsname,
                   exname=exname,
                   exkwargs={
                       'eps': 0.0,
                       'jend': 1
                   })
rr.run()

# check size
kss = KSSingles('rraman-d0.010.eq.ex.gz')
assert (len(kss) == 1)

rr = ResonantRaman(
    H2,
    KSSingles,
    gsname=gsname,
    exname=exname,
    verbose=True,
Esempio n. 8
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c = 5.0
H2 = Atoms([
    Atom('H', (a / 2, a / 2, (c - R) / 2)),
    Atom('H', (a / 2, a / 2, (c + R) / 2))
],
           cell=(a, a, c))

calc = GPAW(xc=xc, nbands=3, spinpol=False, eigensolver='rmm-diis', txt=txt)
H2.set_calculator(calc)
H2.get_potential_energy()

gsname = exname = 'rraman'
exkwargs = {'eps': 0.0, 'jend': 1}
pz = ResonantRaman(H2,
                   KSSingles,
                   gsname=gsname,
                   exname=exname,
                   exkwargs=exkwargs,
                   overlap=lambda x, y: Overlap(x).pseudo(y))
pz.run()

# check size
kss = KSSingles('rraman-d0.010.eq.ex.gz')
assert (len(kss) == 1)

om = 5

# Does Albrecht A work at all ?
# -----------------------------

al = Albrecht(H2,
              KSSingles,