def set_cn_energies( self, cn_energies ):
        """
        Set the coordination number dependent energies for this lattice.

        Args:
            cn_energies (Dict(Str:Dict(Int:Float))): Dictionary of dictionaries specifying the coordination number dependent energies for each site type. e.g.::

                { 'A' : { 0 : 0.0, 1 : 1.0, 2 : 2.0 }, 'B' : { 0 : 0.0, 1 : 2.0 } }

        Returns:
            None
        """
        for site in self.sites:
            site.set_cn_occupation_energies( cn_energies[ site.label ] )
        self.cn_energies = cn_energies