constraint and virtual atom

Carlos carl... at
Thu Oct 18 09:29:49 UTC 2012

Dear CP2K users,

I am trying to do a run using a flexible version of a 4-site water model.  
I am trying to use the &CONSTRAINT module to describe a virtual atom (MW) 
as a function of the O-H distances but I do not want the whole water 
molecule treated as a rigid body. I have specified the virtual atom 
constraint using the &VIRTUAL_SITE definition but I have commented other 
constraints regarding the water molecule. However, I am unable to make it 
work. Could you please have a look at it and let me know what I am doing 
wrong or whether it is possible or not?  

Thanks very much for any help,


 I have attached the input files and below is the error I get

 *** ERROR in get_molecule (MODULE molecule_types_new) ***

 *** The pointer lci is not associated ***

 *** Program stopped at line number 279 of MODULE molecule_types_new ***

 ===== Routine Calling Stack ===== 

            3 velocity_verlet
            2 qs_mol_dyn_low
            1 CP2K
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