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

Abstract

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 (μ = 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.