Dear Hena, a description of various transformations that are in use in crystallography and corresponding matrices can be found in the article Tcl/Tk-based programs. II. CONVROT: a program to recalculate different rotation descriptions Urzhumtseva, L.Mhttp://www.deepdyve.com/search?author=Urzhumtseva%2C+L.M; Urzhumtsev, A.Ghttp://www.deepdyve.com/search?author=Urzhumtsev%2C+A.G http://www.deepdyve.com/lp/international-union-of-crystallography/tcl-tk-bas...Journal of Applied Crystallographyhttp://www.deepdyve.com/browse/journals/journal-of-applied-crystallography , Volume 30 (3): 402 With best regards, Sacha Urzhumtsev ________________________________ De : [email protected] [[email protected]] de la part de Hena Dutta [[email protected]] Date d'envoi : mercredi 25 mai 2011 20:41 À : PHENIX user mailing list Objet : [phenixbb] Equations of transformation Dear Members, Sorry, if my question is out of the field. I want to know the mathematical relations between 2 sets of co-ordinates, one before and one after the rotation. I used COOT to rotate the side chain (containing atoms N1, C2, N3, C4, C5, C6, N6, N7 and C8) of Adenine by 180 degree about the glycosidic bond (C1’-N9). How the initial co-ordinates (Xi, Yi, Zi) and final co-ordinates (Xf, Yf, Zf) are mathematically related? I shall be very grateful if someone can tell me the equations. Regards... Hena