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Simulated-1g1c: Difference between revisions
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"This crystal form contains two molecules in the asymmetric unit. They are related by a noncrystallographic two-fold axis, parallel to the crystallographic b axis, located at X = 0.25 and Z = 0.23. This arrangement results in a peak in the native Patterson map at U = 0.5, V = 0, W = 0.47 of peak height 26 σ (42% of the origin peak)." | "This crystal form contains two molecules in the asymmetric unit. They are related by a noncrystallographic two-fold axis, parallel to the crystallographic b axis, located at X = 0.25 and Z = 0.23. This arrangement results in a peak in the native Patterson map at U = 0.5, V = 0, W = 0.47 of peak height 26 σ (42% of the origin peak)." | ||
Unfortunately, the arrangement of substructure sites has translational symmetry, and may be related to a centrosymmetric arrangement. Indeed, the original structure was solved using molecular replacement. | Unfortunately, the arrangement of substructure sites has (pseudo-)translational symmetry, and may be related to a centrosymmetric arrangement. Indeed, the original structure was solved using molecular replacement. | ||
Using the four sites as given by SHELXE (and default parameters otherwise), I obtained from the [http://cci.lbl.gov/cctbx/phase_o_phrenia.html cctbx - Phase-O-Phrenia server] the following | Using the four sites as given by SHELXE (and default parameters otherwise), I obtained from the [http://cci.lbl.gov/cctbx/phase_o_phrenia.html cctbx - Phase-O-Phrenia server] the following | ||
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... | ... | ||
so the strongest peak corresponds to the translation of molecules (0,0.5,0) but the origin peak is at 1/2 of that size, which appears significant. | so the strongest peak corresponds to the translation of molecules (0,0.5,0) but the origin peak is at 1/2 of that size, which appears significant. | ||