A new scale of electronegativity based on X-ray spectroscopic data was earlier presented by Mande and others for the elements₃Li to₅₄Xe. The present paper reports an extension of this scale carried out for most of the heavier elements lying between₅₅Cs and₉₂U. The present approach is based on the physical interpretation of electronegativity of an atom as the attractive electrostatic force it exerts at a distance equal to its covalent radius. To estimate this force, experimental spectroscopic data have been employed. The merits of such an approach have been pointed out recently by Mullay and may be of interest in the context of the intimate relation found between electronegativity and superconducting transition temperature.