Re: [ccp4bb]: ligands in a 2-fold axis

["Petr Skokan/UPC" <Petr.Skokan@upc.es>]

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Hi,

We have  had similar problem with the ligand on the crystallographic axis.
he only think you have to do in CNS is to exclude PVDW (packing Van der
Waals term)
in the igroup statement (in the input script). Then set the
occupancy to 0.5 to have it there just once. It seems to work.. if I am
wrong
I would appreciate anyone to tell me other possibility....

                                Regards,  Petr.

Here is an example how to  do it (segid H is that ligand on the axis):


igroup

interaction (known and not segid H) (known)
interaction (known and not segid H) (segid H)
interaction (segid H)(segid H) weights * 1.0 pvdw 0

end