def Dadgostar_Shaw_terms(similarity_variable):
    """
    Return terms for the computation of Dadgostar-Shaw heat capacity equation.

    Parameters
    ----------
    similarity_variable : float
        Similarity variable, [mol/g]

    Returns
    -------
    first : float
        First term, [-]
    second : float
        Second term, [-]
    third : float
        Third term, [-]

    See Also
    --------
    Dadgostar_Shaw

    """
    a = similarity_variable
    a2 = a*a
    a11 = -0.3416
    a12 = 2.2671
    a21 = 0.1064
    a22 = -0.3874
    a31 = -9.8231E-05
    a32 = 4.182E-04
    # Didn't seem to improve the comparison; sum of errors on some
    # points included went from 65.5  to 286.
    # Author probably used more precision in their calculation.
    #    constant = 3*R*(theta/T)**2*exp(theta/T)/(exp(theta/T)-1)**2
    constant = 24.5
    return (constant * (a11*a + a12*a2),
            a21*a + a22*a2,
            a31*a + a32*a2)