<div dir="ltr">On Thu, Nov 7, 2013 at 3:50 PM, Ryan Spencer <span dir="ltr"><<a href="mailto:rspencer@uci.edu" target="_blank">rspencer@uci.edu</a>></span> wrote:<br><div class="gmail_extra"><div class="gmail_quote">
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div lang="EN-US" link="blue" vlink="purple"><p class="MsoNormal"><span style="color:rgb(31,73,125);font-family:Calibri,sans-serif;font-size:11pt">I have found that phenix.model_vs_data does not deal well with a perfect twin data set. The refined data is:</span><br>
</p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u>�<u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">��������������� r_work=0.2013 r_free=0.2298 (in PDB file)<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">��������������� r_work=0.2815 r_free=0.3006 (from phenix.model_vs_data)<u></u><u></u></span></p><p class="MsoNormal">
<span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u>�<u></u></span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">There is one merohedral twin operator: -h-k,k,-l (48%) and 6 very small (<1.0%) pseudo-merohedral twin operators.</span></p>
</div></blockquote><div><br></div><div>Yes, the automatic twinning detection is one of the weak points of the current Table 1 program (and the enhanced MolProbity validation in Phenix); a more flexible approach will be available soon. �However, if you have a case where you're certain the structure is twinned (and these R-factors do support that hypothesis) but Phenix is missing it, we'd be interested in seeing the model and data. �It may just be a limitation of the twinning, but occasionally our code trips on corner cases, or it could be something stranger misdiagnosed as twinning.</div>
<div><br></div><div>-Nat</div></div></div></div>