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Dear Phenix users,<br><br>I am currently using version 1.6.1-353 and I'm working on a 1.7A structure that has refined quite well using Individual_sites+individual_adp(isotropic)+occupanices+TLS: Final R-work = 0.1776, R-free = 0.2262<br><br>However, I noticed that the average B-factor reported by polygon with these settings was quite high ( < 0.1 of other structures with a similar resolution).<br><br>Discovering I could not change the value of wxu_scale when using individual_adp+TLS, I went about trying to reduce the average B using the method described here:<br><br>http://phenix-online.org/pipermail/phenixbb/2007-September/000511.html<br><br>However, I still can't seem to reduce the average B-factor. I've just done a refinement with the following non-default (extreme) target weight settings:<br><br> target_weights {<br> wxc_scale = 1.5<br> fix_wxc = 2<br> fix_wxu = 0.1<br> (wxu_scale = 1)<br><br>But if anything, reducing wxu to such low values makes the avergae B-even higher while concuretnly making the gap between R-values much worse:<br><br>Final R-work = 0.1602, R-free = 0.2457<br><br>This suggests to me that I'm obviously over fitting the data but I'm at a loss on how to proceed. Should i just accept that the automatic scaling used for Phenix TLS wxu is doing a good job and that my structure actually does have an unusually high avergae B? <br><br>I'm fitting two ligands into density, which is at several places ambiguous, so I would like the most unbiased difference density possible.<br><br>Many thanks in advance,<br><br>Joe. <br><br> <br /><hr />Find it at CarPoint.com.au <a href='http://clk.atdmt.com/NMN/go/206222968/direct/01/' target='_new'>New, Used, Demo, Dealer or Private?</a></body>
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