CCL: p21/n space group

 Sent to CCL by: Jacco van de Streek [jacco.vandestreek[#]sund.ku.dk]
 >                  I have found  in literature,the  crystal analysis of a
 compound have been done by using p21/n space group, so due to similar structure
 i also want to use this space group form my molecule for crystal structure
 pridiction calculations using  material studio software but i have checked it in
 poly morph pridiction calculation box in the material studio , this space group
 is not present there , from internet i also found that p21/n and p21/c also same
 to some extent , then can i use p21/c instead of p21/n, by the way i have used
 p21/c but structure seems strange.
 > so please guide me about this space group , also tell me how can i use this
 space group p21/n in material studio, that i need it .
 P21/c and P21/n are the same space group, just in different settings. Any
 crystal structure described in P21/c can also be described in P21/n and vice
 versa. P21/c is the standard setting and that is therefore the setting offered
 by the Polymorph Predictor in Materials Studio.
 "Predicting" a crystal structure by only searching in the experimental
 space group is not really a prediction. And from what you write, I get the
 impression that your molecule is only similar to, but not identical to, the
 other molecule, in which case there is no reason why they should have the same
 space group. And what does "structure seems strange" mean? After
 energy-minimisation with a force field (when done properly), a crystal structure
 should look acceptable.
 Best wishes,
 --
 Dr Jacco van de Streek
 Department of Pharmacy
 University of Copenhagen