A synchrotron X-ray diffraction study of a small congruent LiNbO3 crystal:A compatible approach to powder diffraction

Single-crystal synchrotron X-ray diffraction (XRD) data were collected and refined for congruent lithium niobate crystals 8 and 6 mum in diameter, siz es that are comparable to the size of the powder particles used in powder d iffraction. The motivation for using such small crystals is to minimize pro blems such as extinction, which decrease with crystal size. The R/wR factor s were 0.011/0.014 and 0.019/0.018, for the 8 and 6 mum data, respectively, and the goodness of fit factors were 2.3(1) and 1.63(8), which compare fav orably with values obtained from previous powder and single-crystal diffrac tion studies. Results from single-crystal XRD using crystals less than 10 m um in size may rival those obtained from powder diffraction. (C) 2001 Inter national Centre for Diffraction Data.