1c Correlation energy and potential as determined via the local 2c density functional of Vosko, Wilk and Nusair (Can. J. of Phys. 58, 3c 1200 (1980)), functional IV. 4* 5* $Id$ 6* 7#define FNL_VWN_4 8#include "xc_vwn_a.fh" 9c 10c Compute the function deltaEc(rs,zeta) function and its derivatives 11c wrt rs and zeta for the spin-unrestricted case - the rest has the 12c same form for all VWN functionals and is handled in the header files. 13c 14 dec_rsz = devwn_rsz 15 d1dec_rsz(1) = d1devwn_rsz(1) 16 d1dec_rsz(2) = d1devwn_rsz(2) 17#ifdef SECOND_DERIV 18 d2dec_rsz(1) = d2devwn_rsz(1) 19 d2dec_rsz(2) = d2devwn_rsz(2) 20 d2dec_rsz(3) = d2devwn_rsz(3) 21#endif 22#ifdef THIRD_DERIV 23 d3dec_rsz(1) = d3devwn_rsz(1) 24 d3dec_rsz(2) = d3devwn_rsz(2) 25 d3dec_rsz(3) = d3devwn_rsz(3) 26 d3dec_rsz(4) = d3devwn_rsz(4) 27#endif 28c 29#include "xc_vwn_b.fh" 30c 31#ifndef SECOND_DERIV 32#define SECOND_DERIV 33c 34c Compile source again for the 2nd derivative case 35c 36#include "xc_vwn_4.F" 37#endif 38#ifndef THIRD_DERIV 39#define THIRD_DERIV 40c 41c Compile source again for the 3rd derivative case 42c 43#include "xc_vwn_4.F" 44#endif 45