Source code for dxtb._src.param.repulsion

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"""
Parametrization: Repulsion
==========================

Definition of the repulsion contribution. The :class:`EffectiveRepulsion` is
used in GFN1-xTB and GFN2-xTB.
"""

from __future__ import annotations

from typing import Optional

from pydantic import BaseModel

__all__ = ["EffectiveRepulsion", "Repulsion"]




class EffectiveRepulsion(BaseModel):
    """
    Representation of the repulsion contribution for a parametrization.
    """

    kexp: float
    """
    Scaling of the interatomic distance in the exponential damping function of
    the repulsion energy.
    """

    klight: Optional[float] = None
    """
    Scaling of the interatomic distance in the exponential damping function of
    the repulsion energy for light elements, i.e., H and He (only GFN2).
    """





class Repulsion(BaseModel):
    """
    Possible repulsion parametrizations. Currently only the GFN1-xTB effective
    repulsion is supported.
    """

    effective: EffectiveRepulsion
    """Name of the represented method"""