Source code for gpaw.xc

from gpaw.xc.libxc import LibXC
from gpaw.xc.lda import LDA
from gpaw.xc.gga import GGA
from gpaw.xc.mgga import MGGA
from gpaw.xc.noncollinear import NonCollinearLDAKernel


def xc_string_to_dict(string):
    """Convert XC specification string to dictionary.

    'name:key1=value1:...' -> {'name': <name>, key1: value1, ...}."""
    tokens = string.split(':')

    d = {'name': tokens[0]}
    for token in tokens[1:]:
        kw, val = token.split('=')
        # Convert value to int or float if possible
        try:
            val = int(val)
        except ValueError:
            try:
                val = float(val)
            except ValueError:
                pass
        d[kw] = val
    return d


[docs]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, str): 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 == 'ri': # Note: It is important that this if is before the next name is # HSExx, since otherwise PWHybrid would hijack the control flow. from gpaw.xc.ri import RI return RI(name, **kwargs) elif backend == 'pw' or name in ['HSE03', 'HSE06']: from gpaw.hybrids import HybridXC return HybridXC(name, **kwargs) elif backend: raise ValueError( 'A special backend for the XC functional was given, ' 'but not understood. Please check if there is a typo.') 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 == '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 ( get_nonlocal_functional) xc = get_nonlocal_functional(name, **kwargs) 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', 'revTPSS', 'M06-L'}: from gpaw.xc.kernel import XCKernel kernel = XCKernel(name) elif name in {'LDA', 'PBE', 'revPBE', 'RPBE', 'PW91'}: 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)