Elucidating the Crystal Structure of dl-Arginine by Combined Powder X-ray Diffraction Data Analysis and Periodic DFT-D Calculations

摘要

src="http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/cgdefu/2018/cgdefu.2018.18.issue-1/acs.cgd.7b01412/20171227/images/medium/cg-2017-014125_0006.gif">Among the 20 directly encoded proteinogenic amino acids, arginine is one of five remaining cases for which the crystal structure of a racemic crystalline phase has not yet been reported. In this paper, the crystal structure of dl-arginine is determined by exploiting modern methods for analysis of powder X-ray diffraction data, in conjunction with periodic DFT-D calculations. The crystal structure of dl-arginine provides interesting contrasts and comparisons to that of the enantiomerically pure crystalline phase (l-arginine), which was also determined recently from powder X-ray diffraction data.