Source code for dxtb._src.param.charge

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"""
Parametrization: Electrostatics (2nd order)
===========================================

Definition of the isotropic second-order charge interactions.
"""

from __future__ import annotations

from pydantic import BaseModel

from dxtb._src.constants.xtb import DEFAULT_ES2_GEXP

__all__ = ["ChargeEffective", "Charge"]




class ChargeEffective(BaseModel):
    """
    Representation of the isotropic second-order charge interactions for a
    parametrization.
    """

    gexp: float = DEFAULT_ES2_GEXP
    """Exponent of Coulomb kernel. """

    average: str = "harmonic"
    """Averaging function for Hubbard parameter."""





class Charge(BaseModel):
    """
    Possible charge parametrizations. Currently only the interaction kernel
    for the Klopman-Ohno electrostatics (effective) is supported.
    """

    effective: ChargeEffective
    """Klopman-Ohno electrostatics."""