DEMON ANGEL - A SUITE OF PROGRAMS TO CARRY OUT DENSITY MODIFICATION/

The DEMON/ANGEL suite of computer programs has been developed to carry out density modification by non-crystallographic symmetry-averaging, solvent-flattening and histogram-mapping techniques. This suite consis ts of programs that allow molecular envelopes to be defined and modifi ed, non-crystallographic symmetry operators to be refined either withi n one crystal form or between several crystal forms, and iterative den sity modification to be carried out, including non-crystallographic sy mmetry averaging of electron densities within or between crystal forms .