Hi all, I was using SHELXL for the refinement of a small peptide molecule (6-7 residues), and it was working for the first round. But then it gave me an error message. I don't know what's going on and have you had the same problems? Can you give me some suggestions?
*For more information*: I was using coot to read in .fcf and .res file, and after model building, coot can generate an .ins file. I was using this .ins file and the original .hkl for the next round of SHELXL, except I added one line "ANIS" in the .ins file: "DEFS 0.02 0.1 0.01 0.04 CGLS 10 -1 SHEL 10 0.1 FMAP 2 PLAN 200 2.3 LIST 6 WPDB 2 *ANIS*" I checked the working .ins and not-working (generated from coot) .ins files, 1)* the working .ins* (generated from .res file at the very beginning) has: "WGHT 0.100000 SWAT 1.352762 2.1931 FVAR 2.6206 0.5 0.5 0.5 0.5" 2) *the not-workind(generated from coot) .ins* has: "WGHT 0.1 FVAR 1.00000" *The refinement is shown as follows:* "Read instructions and data ** Warning: unusual EXTI or SWAT parameter ** ** Warning: 8 bad CHIV instructions ignored ** Data: 6342 unique, 0 suppressed R(int) = 0.0000 R(sigma) = 0.0615 Systematic absence violations: 0 Bad equivalents: 0 wR2 = 0.4370 before cycle 1 for 6058 data and 1690 / 1690 parameters GooF = S = 4.279; Restrained GooF = 5.862 for 2243 restraints Max. shift = 0.259 A for O_1131b Max. dU =-0.409 for O_1131b at 06:08:24 wR2 = 0.7365 before cycle 2 for 6058 data and 1690 / 1690 parameters GooF = S = 12.229; Restrained GooF = 12.221 for 2243 restraints Max. shift = 0.175 A for O_2131a Max. dU =-0.157 for O_5017 at 06:08:25 ** REFINEMENT UNSTABLE **" The other peptide dataset also has similar problem: I was using coot-SHELXL, model building - refinement cycle *successfully for the first 3 rounds*, but then, it gave me an error message: "Read instructions and data ** Warning: unusual EXTI or SWAT parameter ** ** Warning: no match for 1 atoms in CONN ** ** CANNOT RESOLVE ISOR .. O > LAST **" I checked the working .ins and not-working .ins files (both generated from coot this case), 1) the *working .ins*: "WGHT 0.100000 SWAT 1.288932 3.0398 FVAR 2.6472 0.5 0.5" 2) the* not-working .ins*: "WGHT 0.100000 SWAT 1.344708 3.0452 FVAR 2.731 0.54231 0.5409" I was really confused, since I was using coot for model building for other datasets, and the .ins file generated from coot is good for SHELXL, but it didn't work all the time, eg. it work for the first few rounds, then there is a problem. Can you give me some suggestions about what I should do to get the SHELXL running again? Thanks, Lu
