“…It has useful central nervous system activity and shows a wide range of therapeutic effects. Up to now, six crystalline forms of risperidone have been reported (Krochmal et al, 2004;Reddy et al, 2004;Strelice & Nijmegen, 2004) and characterized by X-ray powder diffraction patterns, but only two of their crystal structures (Form A and risperidone hydrochloride hemipentahydrate) have been determined (Peeters et al, 1993;Wang & Pan, 2006). We report here the crystal structure of form B.…”