ADAS Subroutine cxsode

      SUBROUTINE CXSODE( IZ0 , N , L , ZEFF , E0 )
C
C
C-----------------------------------------------------------------------
C
C  ******************* FORTRAN77 SUBROUTINE: CXSODE ********************
C
C  PURPOSE:  PROVIDES BINDING ENERGY OF TERM CENTRE FOR OUTER ELECTRON
C            IN SODIUM LIKE IONS.
C
C            FROM EDLEN (1978) PHYSICA SCRIPTA, 17, 565.
C
C            FINE STRUCTURE FOR L>0 MUST BE ADDED EXTERNALLY.
C
C            THE ROUTINE IS INCOMPLETE - OPERATES FOR SELECTED IONS
C            ONLY.
C
C  CALLING PROGRAM: GENERAL USE
C
C  INPUT : (I*4)  IZ0     = NUCLEAR CHARGE.
C  INPUT : (I*4)  N       = PRINCIPAL QUANTUM NUMBER.
C  INPUT : (I*4)  L       = ORBITAL QUANTUM NUMBER.
C
C  OUTPUT: (R*8)  ZEFF    = EFFECTIVE CHARGE FOR SPIN-ORBIT SEPAR.
C                           (= ION CHARGE + 1 USUALLY).
C  OUTPUT: (R*8)  E0      = BINDING ENERGY (+VE FOR BOUND STATES).
C                           UNITS: RYD
C
C  PARAM : (I*4)  MXQ     = MAXIMUM ION INDEX FOR QUANTUM DEFECTS DATA.
C  PARAM : (I*4)  MXT     =
C
C          (I*4)  IZ1     = IZ0-10.
C          (I*4)  K       = ARRAY INDEX.
C          (I*4)  IZ1     = LOOP INDEX.
C
C          (R*8)  Z0      = REAL VALUE = IZ0.
C          (R*8)  XN      = REAL VALUE = N.
C          (R*8)  XL      = REAL VALUE = L.
C          (R*8)  R       =
C          (R*8)  A       =
C          (R*8)  B       =
C          (R*8)  C       =
C          (R*8)  S       =
C          (R*8)  U       =
C          (R*8)  U0      =
C          (R*8)  V       =
C          (R*8)  TNL     =
C          (R*8)  AK      =
C          (R*8)  DP      =
C
C          (I*4)  ITAB()  = LOOK UP TABLE FOR QUANTUM DEFECTS DATA.
C                           = 0 : NO DATA PRESENT.
C                           = 1 : DATA PRESENT.
C                           DIMENSION: ION CHARGE INDEX ( = Z+1 ).
C
C          (R*8)  STAB(,) = QUANTUM DEFECTS FOR S.
C                           1ST DIMENSION: 3
C                           2ND DIMENSION: ION CHARGE INDEX ( = Z+1 ).
C          (R*8)  PTAB(,) = QUANTUM DEFECTS FOR P.
C                           1ST DIMENSION: 3
C                           2ND DIMENSION: ION CHARGE INDEX ( = Z+1 ).
C          (R*8)  DTAB(,) = QUANTUM DEFECTS FOR D.
C                           1ST DIMENSION: 3
C                           2ND DIMENSION: ION CHARGE INDEX ( = Z+1 ).
C
C ROUTINES:
C          ROUTINE    SOURCE    BRIEF DESCRIPTION
C          -------------------------------------------------------------
C          I4UNIT     ADAS      RETURNS UNIT NO. FOR OUTPUT OF MESSAGES.
C          R8P        ADAS
C          R8QP       ADAS
C
C AUTHOR:  JONATHAN NASH (TESSELLA SUPPORT SERVICES PLC)
C          K1/0/81
C          JET EXT. 5183
C
C DATE:    03/11/93
C
C-----------------------------------------------------------------------
C
C-----------------------------------------------------------------------
      INTEGER             IZ0,         L,           N
      REAL*8              E0,          ZEFF