Comparison of the accuracy of powder and single-crystal X-ray diffraction techniques in determining organic crystal structure  

作　　者：Shanshan Li Xiaoqing Wu Qingqing Pan Qiang Cheng Hui Li 

机构地区：[1]College of Chemical Engineering, Sichuan University

出　　处：《Chinese Science Bulletin》2014年第5期497-501,共5页

摘　　要：This study demonstrates the accuracy of powder X-ray diffraction(PXRD)in determining the crystal structures of four organic molecules by comparing the structural information obtained from both single-crystal X-ray diffraction(SXRD)and PXRD techniques.Results showed that the PXRD technique had approximately the same precision as the SXRD technique.The majority of the relative deviations from PXRD-derived lattice parameters were within±0.2%of the correct values(average of the SXRD data),whereas the relative deviations in bond lengths and angles are within±1.0%.All of the relative deviations were subjected to normal statistical distributions(l=0)and coincided with the SXRD data.As an auxiliary implement of SXRD,PXRD is clearly an effective and powerful technique in establishing an accurate characterization of organic molecules.This study demonstrates the accuracy of pow- der X-ray diffraction （PXRD） in determining the crystal structures of four organic molecules by comparing the structural information obtained from both single-crystal X-ray diffraction （SXRD） and PXRD techniques. Results showed that the PXRD technique had approximately the same precision as the SXRD technique. The majority of the relative deviations from PXRD-derived lattice parameters were within 4-0.2 % of the correct values （average of the SXRD data）, whereas the relative deviations in bond lengths and angles are within 4-1,0 %, All of the relative deviations were subjected to normal statistical distributions （# = 0） and coincided with the SXRD data. As an auxiliary implement of SXRD, PXRD is clearly an effective and powerful technique in establishing an accurate character- ization of organic molecules.

关 键 词：X-射线衍射技术 单晶X-射线衍射 晶体结构 精度 SXRD 粉末 相对偏差 有机分子 

分 类 号：O72[理学—晶体学]