def thermal_diffusivity(tc, density, Cp):
    """
    calc.thermal_diffusivity

    Calculation of thermal diffusivity

    Args:
        tc: thermal conductivity (float, W/(m K))
        density: (float, g/cm^3)
        Cp: isobaric heat capacity (float, J/(kg K))

    Return:
        Thermal diffusivity (float, m^2/s)
    """
    td = tc / (density * 1e3 * Cp)
    return td