Abstract
For pt.II see ibid., vol.18, p.4471 (1985). The authors have further advanced the study of the spin-dependent features of electron correlations by means of an interpolation that treats in a unified way long- and short-range correlations together with their exchange effects. The correlation energy evaluated from the present interpolation is in excellent agreement with that of Ceperley and Alder (1980) throughout the whole region of metallic densities. They have given some criticisms on the present interpolation a la Hubbard and cleared up its application limit. A detailed examination of the contribution from multi-pair excitations beyond the scope of the present interpolation has been given.