Dear Jacqueline, To calculate the esds of torsion angles correctly for small (or large) molecules you need to do a full-matrix refinement. Rumor has it that there is a refinement program called SHELXL that can do this; the instruction CONF generates torsion angles and their esds (see also the sigi example in chapter 3 of the SHELX manual). For the output of torsion angles and their esds when refining macromolecules with SHELXL the RTAB instruction produces more convenient tables.
Best wishes, George Prof. George M. Sheldrick FRS Dept. Structural Chemistry, University of Goettingen, Tammannstr. 4, D37077 Goettingen, Germany Tel. +49-551-39-3021 or -3068 Fax. +49-551-39-22582 On Sat, 12 Jul 2008, Jacqueline Vitali wrote: > Dear colleagues, > > Does anyone have a copy of the old program DSCAN or MSCAN by S.T. Rao? > > It calculates torsion angles in small molecules. > > Alternatively, does anyone have a program to calculate torsion angles > and their ESD's for small molecules? > > Thanks. > > Jackie Vitali >
