H     H atom (Programme GRIN will adjust parameters for H-bonds) 

   B     Neutral trivalent boron not bonded to hydrogen 
   B-1   Boron in a mono-anion and not directly bonded to hydrogen

   C0    Aliphatic sp3 C atom not bonded to any H atoms 
   C1    Aliphatic sp3 C atom bonded to one H atom
   C2    Aliphatic sp3 C atom bonded to two H atoms 
   C3    Aliphatic sp3 C atom bonded to three H atoms 
   C     Neutral sp2 amide or Carbonyl etc C atom not bonded to H 
   C=    Aromatic or olefin sp2 C atom not bonded to any H atoms
   C1=   Aromatic or olefin sp2 C atom bonded to one H atom 
   C2=   Olefin sp2 C atom bonded to two H atoms
   C+1   sp2 guanidinium etc C not bonded to H (in a cation)
   C-1   sp2 carboxy etc C atom not bonded to H (in an anion) 
   C-2   sp2 Carbonate etc C atom not bonded to H (double anion)
   CH    Neutral sp2 aldehyde etc C atom bonded to one H atom 
   C-H   sp2 formate etc C atom bonded to one H atom (anion)
   C#    sp C atom not bonded to any hydrogens (allyl or acetylene) 
   C1#   sp C atom bonded to one H atom (eg acetylene)
   C:#   sp C with 1 Lone Pair and one triple bond (anion)

  SI     Neutral tetra-valent silicon not bonded to hydrogen
  SI-1   Silicon in a mono-anion and not directly bonded to hydrogen
  SI-2   Silicon in a di-anion and not directly bonded to hydrogen
  SI-3   Silicon in a tri-anion and not directly bonded to hydrogen 
  SI-4   Silicon in a tetra-anion and not directly bonded to hydrogen 
         The above silicon values are not to be used for Zeolites 

   N+    Cationic sp3 N atom bonded to four non-H atoms 
   N1+   Cationic sp3 N atom bonded to 1 H and three other atoms
   N2+   Cationic sp3 N atom bonded to 2 H and two other atoms
   N3+   Cationic sp3 N atom bonded to 3 H and one other atom (R) 
   N:    sp3 N atom with 1 LP bonded to 3 non-H atoms 
   N1:   sp3 N with 1 LP bonded to 1 H and 2 other atoms
   N1<   Like N1: but with inversion of H and lone pair 
   N2:   sp3 N with 1 LP bonded to 2 H and 1 other atom(R)
   N=    Cationic sp2 N with 1 double bond and no H atoms 
   N1=   Cationic sp2 N with 1 H, 1 other single and one double bond
   N2=   Cationic sp2 N bonded to 2 H and with one other double bond
   N0    Planar neutral N bonded to three non-H atoms; eg: nitro
   N1    Planar neutral amide N bonded to 1 H and two other atoms 
   N2    Planar neutral N bonded to 2 H and one other atom
   N:=   Neutral sp2 N with 1 LP 1 non-H single and 1 double bond 
   NH=   Neutral sp2 N with 1 LP 1 H and 1 double bond
   N::   Anionic sp2 N with 2 LP making one double bond 
   N#    sp N atom making two double bonds to (non-H) atoms, or
                one triple bond and one non-H single bond 
   N:#   sp N atom with 1 LP and 1 triple (non-H) bond
   N1#   sp N atom with one triple bond and one single bond to H
   N-1   Nitrogen in a mono-anion not bonded to H (eg: nitrate ion) 
   N-:   sp2 Nitrogen explicitly for 1 and 4 of anionic tetrazole 

   P     Neutral tri or penta-valent phosphorus not bonded to H 
   P+1   Phosphorus in a mono-cation and not directly bonded to H 
   P-1   Phosphorus in a mono-anion and not directly bonded to H
   P-2   Phosphorus in a double anion and not directly bonded to H
   P-3   Phosphorus in a triple anion and not directly bonded to H

  AS     Neutral tri or penta-valent arsenic not bonded to H

  SB     Neutral tri or penta-valent antimony not bonded to H 

   O     sp2 Carbonyl oxygen bonded to 1 atom and with 2 LP 
                e.g.: in aldehyde or ketone or amide groups
   O::   Resonating sp2 oxygen with 2 LP
                i.e. carboxy 
   O#    Explicit oxygen of cyanate accepting one Hbond 
   O-    sp2 anionic oxygen as in phenolate.
                NOT carboxy, NOT phosphate, NOT sulphate.
   O=    Oxygen bonded to 1 atom accepting upto 2 H bonds.
                e.g.: in phosphate or arsenate.
   OH    Oxygen atom bearing one acidic H.
                e.g.: phenol or carboxy -COOH
   O-1   sp3 anionic oxygen as in ethoxide.
   O1    Oxygen atom in sp3 hydroxyl group (R).
   OC2   Aliphatic ether oxygen accepting two H bonds. 
   OC1   Aliphatic and aryl ether oxygen accepting one H bond. 
   OC=   Aryl ether oxygen accepting one H bond.
   OES   Tetrahedral ester oxygen atom not accepting H bonds.
   OFU   Explicit furan or oxazole oxygen accepting one H bond.
   ON    Oxygen of nitro group.
   OS    Oxygen bonded only to one central heavy atom of sulphoxides
                or unionised sulphonate esters or unionised sulphate
                esters or unionised alkyl sulphinates.
                No H.    Does not donate.
   O=S   Oxygen bonded only to one central heavy atom of sulphones or
                sulphates or unionised sulphate or sulphonamides.
   S     Neutral sulphur not bonded to H and not making H-bonds.
                e.g: alkyl sulphates, disulphides, heterocycles,
                sulphimides, sulphoxides, sulphones, unionised
                sulphonamides, sulphoximides.
   S1    Divalent sulphur bonded to one H and one other atom.
   S+1   Sulphur in a mono-cation.  e.g: sulphonium.
   S-    Sulphur in ionized sulphide. eg: CH3.S-
   S-1   Sulphur in a mono-anion and not directly bonded to H 
                e.g: ionised sulphonamides or sulphonates. 
   S-2   Sulphur in a double anion and not directly bonded to H 
                e.g: sulphate.
   SO    Pyramidal sulphur of sulphoxides or unionised sulphinates.
   STH   Explicit aromatic thiophen, thiazole or thioether sulphur. 

  SE     Neutral selenium not bonded to H and not making H-bonds.
  SE1    Divalent selenium bonded to one hydrogen and one other atom.
  SE-1   Selenium in a mono-anion and not directly bonded to hydrogen. 
  SE-2   Selenium in a di-anion and not directly bonded to hydrogen. 

  BR     Bromine atom.
  BR-    Bromide anion.
  CL     Covalent chlorine atom.
  CL-    Chloride anion.
   F     Aliphatic or aromatic fluorine atom accepting up to two H bonds.
   F3    Fluorine atom (CF2,CF3,F-C=C-Fcis) accepting up to two H bonds.
   FS    Fluorine atom bonded to SO or SO2, not accepting H bonds
   F-    Fluoride anion.
   I     Iodine atom.
   I-    Iodide anion. 

  BA+2   Barium cation.
  BE+2   Beryllium cation.
  B+     Boron cation.
  CA+2   Calcium cation.
  CO+2   Divalent cobalt cation.
  CO+3   Trivalent cobalt cation.
  CR+2   Divalent chromium cation. 
  CR+3   Trivalent chromium cation.
  CR+4   Tetravalent chromium cation.
  CS+    Caesium cation.
  CU+2   Divalent copper cation.
  FE+2   Ferrous iron cation.
  FE+3   Ferric iron cation.
  GA+    Monovalent gallium cation.
  GA+3   Trivalent gallium cation.
  GE+4   Tetravalent germanium cation.
  IN+3   Trivalent indium cation.
   K+    Potassium cation.
  LI+    Lithium cation.
  MG+2   Magnesium cation. 
  MN+2   Divalent manganese cation.
  MN+3   Trivalent manganese cation. 
  MN+4   Tetravalent manganese cation. 
  MO+4   tetravalent molybdenum cation.
  NA+    Sodium cation.
  NB+4   Tetravalent niobium cation.
  NB+5   Pentavalent niobium cation. 
  NI+2   Nickle cation.
  PB+2   Divalent lead cation.
  PB+4   Tetravalent lead cation.
  RB+    Rubidium cation.
  SC+3   Scandium cation.
  SN+2   Divalent lead cation.
  SN+4   Tetravalent tin cation.
  SR+2   Strontium cation.
  TI+    Monovalent titanium cation.
  TI+2   Divalent titanium cation.
  TI+3   Trivalent titanium cation.
   V+2   Divalent vanadium cation.
   V+3   Trivalent vanadium cation.
   V+4   Tetravalent vanadium cation.
   W+4   Tetravalent tungsten cation.
   Y+3   Trivalent yttrium cation.
  ZN+2   Zinc cation.
  ZR+4   Zirconium cation.

   OH2   Water (EA).   This is the normal HETATM name for water.

   OHH   Used for the oxygen of water when explicit hydrogen
         coordinates are also given (There must be three separate 
         HETATM records in the Target: one oxygen + two hydrogens 

   O2    Water (EA).   Used when there are many waters in the 
         Target, whose mutual interactions must be considered.