def sigma_Bird_Stewart_Lightfoot_critical_1(Vc):
Vc = Vc*<NUM_LIT>  <EOL>sigma = <NUM_LIT>*Vc**(<NUM_LIT:1>/<NUM_LIT>)<EOL>return sigma<EOL>
r'''Calculates Lennard-Jones molecular diameter.
    Uses critical volume. CSP method by [1]_.

    .. math::
        \sigma = 0.841 V_c^{1/3}

    Parameters
    ----------
    Vc : float
        Critical volume of fluid [m^3/mol]

    Returns
    -------
    sigma : float
        Lennard-Jones molecular diameter, [Angstrom]

    Notes
    -----
    Original units of Vc are mL/mol.

    Examples
    --------
    >>> sigma_Bird_Stewart_Lightfoot_critical_1(0.000268)
    5.422184116631474

    References
    ----------
    .. [1] Bird, R. Byron, Warren E. Stewart, and Edwin N. Lightfoot.
       Transport Phenomena, Revised 2nd Edition. New York:
       John Wiley & Sons, Inc., 2006