c----------------------------------------------------------------------
	subroutine VKS(Eion)
c finds the KS potential from the density, and calculates the
c exchange and correlation contributions
c
c author: Kieron Burke, 8.14.99
c     in: Eion=E(N)-E(N-1)
c	  dens(0:n)
c	  vh(0:m)
c	  vnuc(0:m)
c	  mode
c    out: vks(0:m)
c	  vx(0:m)
c	  vc(0:m)
c  calls:
	include 'basics.inc'
	include 'con.inc'
	include 'dens.inc'
	include 'pot.inc'
	include 'sys.inc'
	dimension dum(0:m)