C ========================================================================
C
C  I.  Common arrays for informations of chemical structure
C
C ------------------------------------------------------------------------
      COMMON /ATOM_STR/ N_PHI,VDW_RAD,ION_RAD,ATM_CHARGE
     *        ,ATM_DIST,ATM_THETA,ATM_PSI
     *        ,IATM_BACK,IATM_FOR,IATM_EXTR,IATM_EXTR2,IATM_EXTR3
     *        ,ID_PHI,ID_TREE,CHEM_TYPE,HB_TYPE,ID_PSI
      REAL      VDW_RAD   (MAXATOM)
      REAL      ION_RAD   (MAXATOM)
      REAL      ATM_CHARGE(MAXATOM)
      REAL      ATM_DIST  (MAXATOM)
      REAL      ATM_THETA (MAXATOM)
      REAL      ATM_PSI   (MAXATOM)
      INTEGER*4 N_PHI   
      INTEGER*4 IATM_BACK (MAXATOM)
      INTEGER*4 IATM_FOR  (MAXATOM)
      INTEGER*4 IATM_EXTR (MAXATOM)
      INTEGER*4 IATM_EXTR2(MAXATOM)
      INTEGER*4 IATM_EXTR3(MAXATOM)
      INTEGER*4 ID_PHI    (MAXATOM)
      INTEGER*4 ID_TREE   (MAXATOM)
      CHARACTER CHEM_TYPE (MAXATOM)*4  
      CHARACTER HB_TYPE   (MAXATOM)*1  
      CHARACTER ID_PSI    (MAXATOM)*4  
C -----------------------------------------------------------
C VDW_RAD    - Van_der_Waals radius.
C ATM_CHARGE - Charge
C
C ATM_DIST   -
C ATM_THETA  - r,theta,psi coordinates
C ATM_PSI    -
C
C IATM_BACK  - tree like structure
C IATM_FOR   -
C IATM_EXTRA -
C
C ID_PHI     - pointer to array  variable angles Phi: PHI_VAR 
C CHEM_TYPE  - chemical type.  
C HB_TYPE    - Type of hydrogen. Donor "D",acceptor "A",both "B" or "N".
C ID_PSI     - id of angle PSI /constant or variable/
C N_PHI      - number of variable angles Phi = Psi
C
C ==========================================================