文献晶体数据改进示例11(金刚烷基无序)
案例来源:J. Org. Chem. 2023, 88, 4345−4351.
DOI:10.1021/acs.joc.2c02944
CCDC:2190301
图形用户界面:Olex2[1](版本:Olex2-1.5)
精修程序:SHELXL[2](版本:SHELXL-2019/2)
CIF文件下载:CCDC[3]官网
根据CCDC号从CCDC官网下到2190301.cif文件,用Olex2打开并提取其hkl和res文件查看,如图1所示,其金刚烷基的碳原子椭球形变严重,周围的Q峰形成另一个金刚烷基构象。

对该基团做二重无序处理,以SAME指令和SIMU指令对其进行限制,最终结果如图2所示。

视频操作演示请参阅:https://www.bilibili.com/video/BV1LC4y1d782
结语
对于明显存在的无序,应当进行适当处理,此举不仅可改善数据指标,还可避免被审稿人打回重新处理而增加时间成本。
参考文献
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