相关软件或概念:Olex2[1] (Version: Olex2-1.5); SHELXL[2] (Version: SHELXL-2019/3); PLATON[3] (Version: 241123) 最近处理组内一个晶体数据,其中频哪醇硼基的碳原子椭球形变严重,最大残余峰Q1处于末端甲基C27的椭球形变方向,残余峰Q2处于末端甲基C25的椭球形变方向,如图1所示。 ▲图1 椭球形变严重的频哪醇硼基 根据椭球形变以及残余峰位置,拟对C25、C26、C24、C27和C28做绕O5–C23健旋转的位置无序,并以SAME指令和SIMU指令分别限制两个组分的几何结构和各向异性位移参数,结果如图2所示,Max Peak从1.0降为0.2,并且R因子也降下来了。 ▲图2 无序处理结果 参考文献 [1]Dolomanov, O. V.; Bourhis, L. J.; Gildea, R. J.; Howard, J. A. K.; Puschmann,H. OLEX2: A complete structure solution,refinement and analysis program. J. Appl. Cryst. 2009, 42, 339–341. [2](a) Sheldrick, G. M. SHELXL-2019/3, Program for Crystal Structure Refinement,University of Göttingen, Germany, 2019. (b) Sheldrick, G. M. A short history ofSHELX. Acta Cryst. 2008, A64, 112–122. (c) Sheldrick, G. M.Crystal structure refinement with SHELXL.Acta Cryst. 2015, C71, 3–8. (d)Lübben, J.; Wandtke, C. M.; Hübschle, C. B.; Ruf, M.; Sheldrick, G. M.;Dittrich, B. Aspherical scattering factors for SHELXL – model, implementation and application. Acta Cryst. 2019, A75, 50–62. [3] (a) Spek, A. L. Single-crystal structure validationwith the program PLATON. J. Appl.Cryst. 2003, 36, 7–13. (b) Spek,A. L. Structure validation in chemical crystallography. Acta Cryst. 2009, D65, 148–155. (c) Spek, A. L. What makes a crystal structure reportvalid? Inorg. Chim. Acta 2018, 470, 232–237. (d) Spek, A. L. checkCIFvalidation ALERTS: what they mean and how to respond. Acta Cryst. 2020, E76, 1–11. 如需PDF文档,请从以下链接下载: 通过网盘分享的文件:无序示例-频哪醇硼基二重无序.pdf
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