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[交流] 急求协助CIF的一个难题

好不容易写好了一篇文章投到ACTA E,可是CO EDITOR提出了一个问题,让我无法解决,请教了几个朋友可是还是没有解决.如果这个问题不解决,文章就被拒掉了,请各位朋友帮帮我哦.我把CO EDITOR的意见粘贴过来,恳请各位赐教.谢谢.The first major remaining problem is the Tmin to tmax ratio. The measured ratio you are giving is much too low for a purely organic compound. This points towards a wrongly conducted absorption correction or a seriously biased dataset. It is possible that you applied much to high values for the even and odd spherical harmonics. The default values are not suitable for an organic compound. The values applied for a molecule without any heavy scatterers should not be higher than 2 for the even value and 1 for the odd value ("weak absorber" if you happen to use the "Scale" routine in Apex2). If this does not give a value much closer to a ratio of 0.9 or higher you can try using two times zero for both spherical harmonics. If that does not help as well you should not apply any absorption at all (use the raw file as the starting point in XPREP rather than the biased hkl file from sadabs).

You will have to re-refine the structure with the reduced or omitted absorption correction and prepare a completely new cif file.
If you do use absorption correction the ratio obtained in sadabs has to be added for Tmin, for Tmax add 1 in the cif file and then run Checkcif. It will suggest a scale factor that you should apply to both Tmin and Tmax. It will also tell whether the experimental values obtained are acceptable or not (there should be no level A or B alert for the Tmin/Tmax ratio).
[search]CIF 问题[/search]
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