| Card | Format | Description | 
| I-1-1 | a1 | $ to identify the start of a fragment | 
| I-1-2 | a10 | name of the fragment, the tenth character | 
|  |  | N: identifies beginning of a chain | 
|  |  | C: identifies end of a chain | 
|  |  | blank: identifies chain fragment | 
|  |  | M: identifies an integral molecule | 
| I-2-1 | i5 | number of atoms in the fragment | 
| For each atom one deck II |  |  | 
| II-1-1 | i5 | atom sequence number | 
| II-1-2 | a6 | atom name | 
| II-1-3 | a5 | atom type | 
| II-1-4 | a1 | dynamics type | 
|  |  |  : normal | 
|  |  | D: dummy atom | 
|  |  | S: solute interactions only | 
|  |  | Q: quantum atom | 
|  |  | other : intramolecular solute interactions only | 
| II-1-5 | i5 | link number | 
|  |  | 0: no link | 
|  |  | 1: first atom in chain | 
|  |  | 2: second atom in chain | 
|  |  | 3 and up: other links | 
| II-1-6 | i5 | environment type | 
|  |  | 0: no special identifier | 
|  |  | 1: planar, using improper torsion | 
|  |  | 2: tetrahedral, using improper torsion | 
|  |  | 3: tetrahedral, using improper torsion | 
|  |  | 4: atom in aromatic ring | 
| II-1-7 | i5 | charge group | 
| II-1-8 | i5 | polarization group | 
| II-1-9 | f12.6 | atomic partial charge | 
| II-1-10 | f12.6 | atomic polarizability | 
| Any number of cards in deck III to specify complete 
connectivity |  |  | 
| III-1-1 | 16i5 | connectivity, duplication allowed |