subroutine surface(v,rij)
!
!   $RCSfile: surface.f,v $ $Revision: 1.3 $
!   $Date: 89/08/07 09:11:25 $
!   $State: Stable $
!
!            P U R P O S E   O F    S U B R O U T I N E

!-----------------------------------------------------------------------
! This routine supplies the potential energy surface for the
! reactive scattering codes.
!
! On entering: The arrary rij contains the internuclear distances
!              in units of bohr (NOT mass scaled).
!
! On Exit:     The variable v is the value of the potential energy
!              surface in Hartree atomic units.
!
!
!-----------------------------------------------------------------------

!            I N P U T    A R G U M E N T S
!    v
!    rij
!            O U T P U T    A R G U M E N T S
 
! <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>
 

      USE PES_Module
      implicit none
      character(LEN=25) potname
	real*8 v, rij
	dimension rij(3)
      external lifh
!-----------------------------------------------------------------------
!  The character string potname must contain a string that uniquely
!  specifies the potential energy surface to be used.
!-----------------------------------------------------------------------
      data potname/'LiFH Bond Order PES'/

!-----------------------------------------------------------------------
! Check for correct potential energy surface specification.
!-----------------------------------------------------------------------
      if(PES_Name.ne.potname)then
         write(6,*)'The potential energy surface name does not match',
     >          ' the name in the potential energy surface routine.'
         write(6,*)'***error***: Execution stopped in routine surface'
         write(6,304)' Name read in from input data:  ',PES_Name
         write(6,304)' Name of the potential energy surface routine:  ',
     >              potname
  304    format(1x,a20)
         stop 'surface'
      end if

!-----------------------------------------------------------------------
! This call to surfac supplies the potential energy surface
! for the particular system of interest.
!-----------------------------------------------------------------------
      call lifh(v,rij)
      return
      end