@property<EOL><INDENT>def Van_der_Waals_area(self):<DEDENT>
if self.UNIFAC_Q:<EOL><INDENT>return Van_der_Waals_area(self.UNIFAC_Q)<EOL><DEDENT>return None<EOL>
r'''Unnormalized Van der Waals area, in units of [m^2/mol].

        Examples
        --------
        >>> Chemical('hexane').Van_der_Waals_area
        964000.0