Hi Faisal,
It looks like your restraints are simply not tight enough. Try optimizing the restraint weight. You should also run more cycles of refinement to make sure it converges. The initial gap between R and R-free is pretty small. Did you do much refinement before this run? Cheers, Robbie From: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] On Behalf Of Faisal Tarique Sent: Monday, July 23, 2012 17:52 To: CCP4BB@JISCMAIL.AC.UK Subject: [ccp4bb] large difference between r & rfree during refinement Dear all i have two basic queries 1> while refining my structure (of resolution 2.2A) i face problem with the gap in R & Rfree which is around 8. The mosaicity of my data is 1.8. is this difference is due to large mosaicity or twinning though for twinning i got nothing when i checked with Xtriage.. Ncyc Rfact Rfree FOM -LL -LLfree rmsBOND zBOND rmsANGL zANGL rmsCHIRAL $$ $$ 0 0.2280 0.2488 0.827 75366. 4001.1 0.0318 1.602 2.061 0.978 0.192 1 0.2023 0.2493 0.828 73747. 3981.8 0.0193 0.966 2.020 0.947 0.136 2 0.1928 0.2506 0.827 73291. 3983.6 0.0183 0.914 2.028 0.952 0.132 3 0.1886 0.2509 0.826 73116. 3986.7 0.0178 0.889 2.021 0.950 0.131 4 0.1860 0.2515 0.824 73050. 3990.8 0.0175 0.872 2.015 0.948 0.131 5 0.1847 0.2524 0.822 73036. 3995.1 0.0172 0.856 2.005 0.944 0.131 6 0.1838 0.2530 0.821 73034. 3998.9 0.0169 0.842 1.993 0.938 0.131 7 0.1832 0.2545 0.819 73046. 4002.6 0.0167 0.832 1.983 0.935 0.130 8 0.1828 0.2553 0.818 73054. 4005.4 0.0165 0.822 1.973 0.931 0.130 9 0.1825 0.2567 0.816 73070. 4008.3 0.0163 0.815 1.964 0.927 0.130 10 0.1824 0.2578 0.815 73085. 4010.8 0.0162 0.807 1.955 0.922 0.130 2> what is the best way to add water during structure solution ?? is it better to do it automatically during refinement in refmac or arpwarp solvent is a better option ?? -- Regards Faisal School of Life Sciences JNU
