Application of Brodie's concept of the work function to simple metals

It is shown that the values of the work function (WF) calculated from Brodie's expression (BE) (I. Brodie, Phys. Rev. B , 51 (1995) 660) agree with those calculated self-consistently for simple metals, by the use of the conventional WF definition. Brodie's concept of the Heisenberg uncertainty distance at the metal surface was used also for testing the distance from the last atomic layer to the image plane of the jellium surface. The variation of WF between crystal faces is shown to be mainly due to the variation of the "atomic" radius for the single-crystal surface rather than to the direction-dependent variation of the effective mass of the electron with the Fermi momentum inside the metal. The WF values calculated under such assumption are close to the experimental ones for fcc, bcc and hcp metals.