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 II. 4* 5* $Id$ 6* 7#define FNL_VWN_2 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 + (dec_rs1-derpa_rs1)*fz 15 d1dec_rsz(1) = d1devwn_rsz(1) + (d1dec_rs1-d1derpa_rs1)*fz 16 d1dec_rsz(2) = d1devwn_rsz(2) + (dec_rs1-derpa_rs1)*d1fz 17#ifdef SECOND_DERIV 18 d2dec_rsz(1) = d2devwn_rsz(1) + (d2dec_rs1-d2derpa_rs1)*fz 19 d2dec_rsz(2) = d2devwn_rsz(2) + (d1dec_rs1-d1derpa_rs1)*d1fz 20 d2dec_rsz(3) = d2devwn_rsz(3) + (dec_rs1-derpa_rs1)*d2fz 21#endif 22#ifdef THIRD_DERIV 23 d3dec_rsz(1) = d3devwn_rsz(1) + (d3dec_rs1-d3derpa_rs1)*fz 24 d3dec_rsz(2) = d3devwn_rsz(2) 25 & + (d2dec_rs1-d2derpa_rs1)*d1fz 26 d3dec_rsz(3) = d3devwn_rsz(3) 27 & + (d1dec_rs1-d1derpa_rs1)*d2fz 28 d3dec_rsz(4) = d3devwn_rsz(4) 29 & + (dec_rs1-derpa_rs1)*d3fz 30#endif 31c 32#include "xc_vwn_b.fh" 33c 34#ifndef SECOND_DERIV 35#define SECOND_DERIV 36c 37c Compile source again for the 2nd derivative case 38c 39#include "xc_vwn_2.F" 40#endif 41#ifndef THIRD_DERIV 42#define THIRD_DERIV 43c 44c Compile source again for the 3rd derivative case 45c 46#include "xc_vwn_2.F" 47#endif 48