[ccp4bb]: fixing atoms in CNS

[Manisha goel <manishag@webnii.nii.res.in>]

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Dear All,
 Though this is not exactly the CCP4 problem, i hope you may be able to
help me.
i am  refining a receptor-ligand structure using CNS, my ligand is a
closed ring consisting of 4 aromatic rings which also contain N atoms.
i want to now fix these Nitrogen atoms and refine the rest of the
structure.
the refinement files like minimize.inp show a section where you can write
the atoms to be fixed, but that doesn't seem to be working in my case.

i have written it as

(N4B and resid XYZ and segid B)
where N4B is the atom i.d.

i think the only problem is the syntax of this line,
Does anybody have any other suggestions,
Please help me!

Thanx a lot !

Goel M.