def __init__(self, name, hybrid=None, xc=None, finegrid=False):
"""Mix standard functionals with exact exchange.
name: str
Name of hybrid functional.
hybrid: float
Fraction of exact exchange.
xc: str or XCFunctional object
Standard DFT functional with scaled down exchange.
finegrid: boolean
Use fine grid for energy functional evaluations?
"""
if name == 'EXX':
assert hybrid is None and xc is None
hybrid = 1.0
xc = XC(XCNull())
elif name == 'PBE0':
assert hybrid is None and xc is None
hybrid = 0.25
xc = XC('HYB_GGA_XC_PBEH')
elif name == 'B3LYP':
assert hybrid is None and xc is None
hybrid = 0.2
xc = XC('HYB_GGA_XC_B3LYP')
if isinstance(xc, str):
xc = XC(xc)
self.hybrid = hybrid
self.xc = xc
self.type = xc.type
self.finegrid = finegrid
XCFunctional.__init__(self, name)
def get_non_xc_total_energies(self):
"""Compile non-XC total energy contributions"""
if self.e_dft is None:
self.e_dft = self.calc.get_potential_energy()
if self.e0 is None:
from gpaw.xc.kernel import XCNull
xc_null = XC(XCNull())
self.e0 = self.e_dft + self.calc.get_xc_difference(xc_null)
assert isinstance(self.e_dft, float)
assert isinstance(self.e0, float)
def __init__(self, name, hybrid=None, xc=None, omega=None):
"""Mix standard functionals with exact exchange.
name: str
Name of hybrid functional.
hybrid: float
Fraction of exact exchange.
xc: str or XCFunctional object
Standard DFT functional with scaled down exchange.
"""
if name == 'EXX':
assert hybrid is None and xc is None
hybrid = 1.0
xc = XC(XCNull())
elif name == 'PBE0':
assert hybrid is None and xc is None
hybrid = 0.25
xc = XC('HYB_GGA_XC_PBEH')
elif name == 'B3LYP':
assert hybrid is None and xc is None
hybrid = 0.2
xc = XC('HYB_GGA_XC_B3LYP')
elif name == 'HSE03':
assert hybrid is None and xc is None and omega is None
hybrid = 0.25
omega = 0.106
xc = XC('HYB_GGA_XC_HSE03')
elif name == 'HSE06':
assert hybrid is None and xc is None and omega is None
hybrid = 0.25
omega = 0.11
xc = XC('HYB_GGA_XC_HSE06')
if isinstance(xc, str):
xc = XC(xc)
self.hybrid = float(hybrid)
self.xc = xc
self.omega = omega
self.type = xc.type
XCFunctional.__init__(self, name)
def __init__(self, name, stencil=2, hybrid=None, xc=None, omega=None):
"""Mix standard functionals with exact exchange.
name: str
Name of hybrid functional.
hybrid: float
Fraction of exact exchange.
xc: str or XCFunctional object
Standard DFT functional with scaled down exchange.
"""
rsf_functionals = { # Parameters can also be taken from libxc
'CAMY-BLYP': { # Akinaga, Ten-no CPL 462 (2008) 348-351
'alpha': 0.2,
'beta': 0.8,
'omega': 0.44,
'cam': True,
'rsf': 'Yukawa',
'xc': 'HYB_GGA_XC_CAMY_BLYP'
},
'CAMY-B3LYP': { # Seth, Ziegler JCTC 8 (2012) 901-907
'alpha': 0.19,
'beta': 0.46,
'omega': 0.34,
'cam': True,
'rsf': 'Yukawa',
'xc': 'HYB_GGA_XC_CAMY_B3LYP'
},
'LCY-BLYP': { # Seth, Ziegler JCTC 8 (2012) 901-907
'alpha': 0.0,
'beta': 1.0,
'omega': 0.75,
'cam': False,
'rsf': 'Yukawa',
'xc': 'HYB_GGA_XC_LCY_BLYP'
},
'LCY-PBE': { # Seth, Ziegler JCTC 8 (2012) 901-907
'alpha': 0.0,
'beta': 1.0,
'omega': 0.75,
'cam': False,
'rsf': 'Yukawa',
'xc': 'HYB_GGA_XC_LCY_PBE'
}
}
self.omega = None
self.cam_alpha = None
self.cam_beta = None
self.is_cam = False
self.rsf = None
def _xc(name):
return {'name': name, 'stencil': stencil}
if name == 'EXX':
hybrid = 1.0
xc = XC(XCNull())
elif name == 'PBE0':
hybrid = 0.25
xc = XC(_xc('HYB_GGA_XC_PBEH'))
elif name == 'B3LYP':
hybrid = 0.2
xc = XC(_xc('HYB_GGA_XC_B3LYP'))
elif name == 'HSE03':
hybrid = 0.25
omega = 0.106
xc = XC(_xc('HYB_GGA_XC_HSE03'))
elif name == 'HSE06':
hybrid = 0.25
omega = 0.11
xc = XC(_xc('HYB_GGA_XC_HSE06'))
elif name in rsf_functionals:
rsf_functional = rsf_functionals[name]
self.cam_alpha = rsf_functional['alpha']
self.cam_beta = rsf_functional['beta']
self.omega = rsf_functional['omega']
self.is_cam = rsf_functional['cam']
self.rsf = rsf_functional['rsf']
xc = XC(rsf_functional['xc'])
hybrid = self.cam_alpha + self.cam_beta
if isinstance(xc, (basestring, dict)):
xc = XC(xc)
self.hybrid = float(hybrid)
self.xc = xc
if omega is not None:
omega = float(omega)
if self.omega is not None and self.omega != omega:
self.xc.kernel.set_omega(omega)
# Needed to tune omega for RSF
self.omega = omega
XCFunctional.__init__(self, name, xc.type)
def __init__(self,
name,
hybrid=None,
xc=None,
finegrid=False,
alpha=None,
skip_gamma=False,
gygi=False,
acdf=True,
qsym=True,
txt=None,
ecut=None):
"""Mix standard functionals with exact exchange.
name: str
Name of hybrid functional.
hybrid: float
Fraction of exact exchange.
xc: str or XCFunctional object
Standard DFT functional with scaled down exchange.
finegrid: boolean
Use fine grid for energy functional evaluations?
"""
if name == 'EXX':
assert hybrid is None and xc is None
hybrid = 1.0
xc = XC(XCNull())
elif name == 'PBE0':
assert hybrid is None and xc is None
hybrid = 0.25
xc = XC('HYB_GGA_XC_PBEH')
elif name == 'B3LYP':
assert hybrid is None and xc is None
hybrid = 0.2
xc = XC('HYB_GGA_XC_B3LYP')
if isinstance(xc, str):
xc = XC(xc)
self.hybrid = hybrid
self.xc = xc
self.type = xc.type
self.alpha = alpha
self.qsym = qsym
self.skip_gamma = skip_gamma
self.gygi = gygi
self.acdf = acdf
self.exx = None
self.ecut = ecut
if txt is None:
if rank == 0:
#self.txt = devnull
self.txt = sys.stdout
else:
sys.stdout = devnull
self.txt = devnull
else:
assert type(txt) is str
from ase.parallel import paropen
self.txt = paropen(txt, 'w')
XCFunctional.__init__(self, name)
a = 4.0
x = Atoms(cell=(a, a, a)) # no atoms
class HarmonicPotential:
def __init__(self, alpha):
self.alpha = alpha
self.vext_g = None
def get_potential(self, gd):
if self.vext_g is None:
r_vg = gd.get_grid_point_coordinates()
self.vext_g = self.alpha * ((r_vg - a / Bohr / 2)**2).sum(0)
return self.vext_g
calc = GPAW(charge=-8,
nbands=4,
h=0.2,
xc=XC(XCNull()),
external=HarmonicPotential(0.5),
poissonsolver=NoInteractionPoissonSolver(),
eigensolver='cg')
x.calc = calc
x.get_potential_energy()
eigs = calc.get_eigenvalues()
equal(eigs[0], 1.5 * Hartree, 0.002)
equal(abs(eigs[1:] - 2.5 * Hartree).max(), 0, 0.003)
def __init__(self,
calc,
xc=None,
kpts=None,
bands=None,
ecut=None,
omega=None,
world=mpi.world,
txt=sys.stdout,
timer=None):
PairDensity.__init__(self,
calc,
ecut,
world=world,
txt=txt,
timer=timer)
if xc is None or xc == 'EXX':
self.exx_fraction = 1.0
xc = XC(XCNull())
elif xc == 'PBE0':
self.exx_fraction = 0.25
xc = XC('HYB_GGA_XC_PBEH')
elif xc == 'HSE03':
omega = 0.106
self.exx_fraction = 0.25
xc = XC('HYB_GGA_XC_HSE03')
elif xc == 'HSE06':
omega = 0.11
self.exx_fraction = 0.25
xc = XC('HYB_GGA_XC_HSE06')
elif xc == 'B3LYP':
self.exx_fraction = 0.2
xc = XC('HYB_GGA_XC_B3LYP')
self.xc = xc
self.omega = omega
self.exc = np.nan # density dependent part of xc-energy
self.kpts = select_kpts(kpts, self.calc)
if bands is None:
# Do all occupied bands:
bands = [0, self.nocc2]
prnt('Calculating exact exchange contributions for band index',
'%d-%d' % (bands[0], bands[1] - 1),
file=self.fd)
prnt('for IBZ k-points with indices:',
', '.join(str(i) for i in self.kpts),
file=self.fd)
self.bands = bands
if self.ecut is None:
self.ecut = self.calc.wfs.pd.ecut
prnt('Plane-wave cutoff: %.3f eV' % (self.ecut * Hartree),
file=self.fd)
shape = (self.calc.wfs.nspins, len(self.kpts), bands[1] - bands[0])
self.exxvv_sin = np.zeros(shape) # valence-valence exchange energies
self.exxvc_sin = np.zeros(shape) # valence-core exchange energies
self.f_sin = np.empty(shape) # occupation numbers
# The total EXX energy will not be calculated if we are only
# interested in a few eigenvalues for a few k-points
self.exx = np.nan # total EXX energy
self.exxvv = np.nan # valence-valence
self.exxvc = np.nan # valence-core
self.exxcc = 0.0 # core-core
self.mysKn1n2 = None # my (s, K, n1, n2) indices
self.distribute_k_points_and_bands(0, self.nocc2)
# All occupied states:
self.mykpts = [
self.get_k_point(s, K, n1, n2) for s, K, n1, n2 in self.mysKn1n2
]
prnt('Using Wigner-Seitz truncated coulomb interaction.', file=self.fd)
self.wstc = WignerSeitzTruncatedCoulomb(self.calc.wfs.gd.cell_cv,
self.calc.wfs.kd.N_c, self.fd)
self.iG_qG = {} # cache
# PAW matrices:
self.V_asii = [] # valence-valence correction
self.C_aii = [] # valence-core correction
self.initialize_paw_exx_corrections()
def XC(kernel, parameters=None, atoms=None, collinear=True):
"""Create XCFunctional object.
kernel: XCKernel object, dict or str
Kernel object or name of functional.
parameters: ndarray
Parameters for BEE functional.
Recognized names are: LDA, PW91, PBE, revPBE, RPBE, BLYP, HCTH407,
TPSS, M06-L, revTPSS, vdW-DF, vdW-DF2, EXX, PBE0, B3LYP, BEE,
GLLBSC. One can also use equivalent libxc names, for example
GGA_X_PBE+GGA_C_PBE is equivalent to PBE, and LDA_X to the LDA exchange.
In this way one has access to all the functionals defined in libxc.
See xc_funcs.h for the complete list. """
if isinstance(kernel, basestring):
kernel = xc_string_to_dict(kernel)
kwargs = {}
if isinstance(kernel, dict):
kwargs = kernel.copy()
name = kwargs.pop('name')
backend = kwargs.pop('backend', None)
if backend == 'libvdwxc' or name == 'vdW-DF-cx':
# Must handle libvdwxc before old vdw implementation to override
# behaviour for 'name'. Also, cx is not implemented by the old
# vdW module, so that always refers to libvdwxc.
from gpaw.xc.libvdwxc import get_libvdwxc_functional
return get_libvdwxc_functional(name=name, **kwargs)
elif backend:
error_msg = "A special backend for the XC functional was given, "\
"but not understood. Please check if there's a typo."
raise ValueError(error_msg)
if name in ['vdW-DF', 'vdW-DF2', 'optPBE-vdW', 'optB88-vdW',
'C09-vdW', 'mBEEF-vdW', 'BEEF-vdW']:
from gpaw.xc.vdw import VDWFunctional
return VDWFunctional(name, **kwargs)
elif name in ['EXX', 'PBE0', 'B3LYP',
'CAMY-BLYP', 'CAMY-B3LYP', 'LCY-BLYP', 'LCY-PBE']:
from gpaw.xc.hybrid import HybridXC
return HybridXC(name, **kwargs)
elif name.startswith('LCY-') or name.startswith('CAMY-'):
parts = name.split('(')
from gpaw.xc.hybrid import HybridXC
return HybridXC(parts[0], omega=float(parts[1][:-1]))
elif name in ['HSE03', 'HSE06']:
from gpaw.xc.exx import EXX
return EXX(name, **kwargs)
elif name == 'BEE1':
from gpaw.xc.bee import BEE1
kernel = BEE1(parameters)
elif name == 'BEE2':
from gpaw.xc.bee import BEE2
kernel = BEE2(parameters)
elif name.startswith('GLLB'):
from gpaw.xc.gllb.nonlocalfunctionalfactory import \
NonLocalFunctionalFactory
# Pass kwargs somewhere?
xc = NonLocalFunctionalFactory().get_functional_by_name(name)
xc.print_functional()
return xc
elif name == 'LB94':
from gpaw.xc.lb94 import LB94
kernel = LB94()
elif name == 'TB09':
from gpaw.xc.tb09 import TB09
return TB09(**kwargs)
elif name.endswith('PZ-SIC'):
from gpaw.xc.sic import SIC
return SIC(xc=name[:-7], **kwargs)
elif name in ['TPSS', 'M06-L', 'M06L', 'revTPSS']:
if name == 'M06L':
name = 'M06-L'
warnings.warn('Please use M06-L instead of M06L')
from gpaw.xc.kernel import XCKernel
kernel = XCKernel(name)
elif name.startswith('old'):
from gpaw.xc.kernel import XCKernel
kernel = XCKernel(name[3:])
elif name == 'PPLDA':
from gpaw.xc.lda import PurePythonLDAKernel
kernel = PurePythonLDAKernel()
elif name in ['pyPBE', 'pyPBEsol', 'pyRPBE', 'pyzvPBEsol']:
from gpaw.xc.gga import PurePythonGGAKernel
kernel = PurePythonGGAKernel(name)
elif name == '2D-MGGA':
from gpaw.xc.mgga import PurePython2DMGGAKernel
kernel = PurePython2DMGGAKernel(name, parameters)
elif name[0].isdigit():
from gpaw.xc.parametrizedxc import ParametrizedKernel
kernel = ParametrizedKernel(name)
elif name == 'null':
from gpaw.xc.kernel import XCNull
kernel = XCNull()
elif name == 'QNA':
from gpaw.xc.qna import QNA
return QNA(atoms, kernel['parameters'], kernel['setup_name'],
alpha=kernel['alpha'], stencil=kwargs.get('stencil', 2))
else:
kernel = LibXC(name)
if kernel.type == 'LDA':
if not collinear:
kernel = NonCollinearLDAKernel(kernel)
xc = LDA(kernel, **kwargs)
return xc
elif kernel.type == 'GGA':
return GGA(kernel, **kwargs)
else:
return MGGA(kernel, **kwargs)
