I am trying to adapt my old CNS scripts to to multiple conformer refinements in Phenix, i.e. up to 20 copies of each entire chain. I seem to be OK with up to three copies of the whole chain, but when I try four or more I seem to be in an infinite loop in the 'reduce' phase of a refinement. 3 copies runs in less than hour, even with torsion simulated annealing, with four even overnight the program just runs 'reduce for hours and hours'. This happens on the standard release and development version 1422. Is there some way to turn off hydrogens as a work around? Test files available on request. : ) Thanks for any help! George George N. Phillips, Jr. Ralph and Dorothy Looney Professor Department of Biochemistry and Cell Biology Rice University, MS140 6100 Main Street Houston, Texas 77005-1892 Office: +1 713.348.6951 http://www.bioc.rice.edu/