Dear all,<br><br>I am refining a structure with a metal ion on a 2-fold axis, coordinated by four histidines, two from the ASU and two from symmetry. I used phenix.ready_set to generate the metal coordination file and input it into phenix.refine. However, phenix.refine complains that the customized angle restraints contain a special position atom and cannot continue. I am using Phenix 1.5.2. Could anyone suggest me how to solve this problem?<br>
<br>Thank you!<br><br>Best,<br><br>Tiancen<br>