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[求助]
l两个B类错误
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PLAT250 PLAT250 Type_2 Test for unusual anisotropic average UIJ An average value of the U(i,j) tensor of the asymmetric unit of a residue is calculated. An ALERT is generated when the corresponding U3/U1 ratio deviates significantly from 1.0. Large values of this ratio should be taken as an indication of possible systematic errors in the data or errors in the model. Visual inspection of an ORTEP plot will show that many displacement ellipsoids have their major axis pointing in the same direction PLAT342 PLAT342 Type_3 Check Bond Precision for C-C in Structures (Z(max) > 39) The average su for X-Y bonds is tested (named bond-precision). X-Y will generally be C-C bonds, unless there are none. In the last case the su's of the lowest element numbers are considered (excluding hydrogen). There are three test ranges: one for structures with the largest element Z < 20, one for the largest Z in the range 20 to 39 and one for structures with Z(max) 40 or higher (_340, _341 and _342 respectively) |
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