FRG | FRA | FRAG
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| Synopsis |
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[-]frg|fra|frag filename |
| Description |
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This keyword allows entering the pathname of the disk file that contains molecular fragment specifications. |
| Aim |
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Evaluation of properties, like moments and electrostatic interaction energies, of specified molecular fragments, in addition to the properties of the molecule itself. |
| Syntax rules for fragment specification |
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Any line beginning with either ! or # is a comment line. An input line can either define a fragment of the current molecule or specify a new molecule. Any fragment-definition line has the following syntax: fragment-label n1 n2 n3-n12 n13 n14-n21 ... where the first field is any character string that itentifies the fragment and the following fields are the sequence numbers of the atoms that belong to the fragment. Atoms can be specified either individually (e.g. n1 n2 ... n13) or through a range of atoms (e.g. n3-n12 ... n14-n21). If the atoms specified in the fragments do not exhaust the list of atoms in the molecule, a new fragment containing the remaining atoms will be added. Fragments can overlap, i.e. they can share atoms. A line starting with NEW, NEXT or MOL specifies the beginning of a new molecule. |
| Example |
!Fragments in LR-B/081: 2-[(4-butyl-2-methyl-6-oxo-5-([2'-(1H-tetrazol-5-yl) !-1,1'-biphenyl-4-yl]methyl)-6H-pyrimidin-1-yl)methyl]-3-thiophencarboxylic !acid methyl ester. tetrazole 7-10 36 41 p-phenyl 24-29 44-47 o-phenyl 30-35 48-51 n-butyl 37-40 62-70 CH3 22 57-59 C(5)H2 15 52 53 C(13)H2 23 60 61 pyr 2 5 6 11-14 C3H7pyr 2 5 6 11-15 22 23 52 53 57-61 COOCH3 3 4 20 21 54-56 tiophene 1 16-19 42 43 C2O2H3tio 1 3 4 16-21 42 43 54-56 C3O2H5tio 1 3 4 15-21 42 43 52-56 |