I am trying to solve a structure by molecular replacement in phaser using 2 model fragments. I think I may have placed the 1st fragment correctly. I don't quite understand how to best proceed with a fixed ensemble searching for the second fragment in phaser-MR. If I select "use partial solution from previous job", do I still need to read in the coordinates of that previous solution for one ensemble? And If I do, should I read in the starting coordinates or the placed output from this 1st molecular replacement? The second question is about how to relax the restraints fr the packing. In the "other settings" sub window is a section for packing. Could someone explain to me what the different options in this packing section mean? Which of them should I change to allow for more close contacts? Thanks Ursula -- Ursula Schulze-Gahmen, Ph.D. Assistant Researcher UC Berkeley, QB3 356 Stanley Hall #3220 Berkeley, CA 94720-3220