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

摘要

Among the 20 directly encoded proteinogenicudamino acids, arginine is one of five remaining cases for whichudthe crystal structure of a racemic crystalline phase has not yetudbeen reported. In this paper, the crystal structure of DLarginineudis determined by exploiting modern methods forudanalysis of powder X-ray diffraction data, in conjunction withudperiodic DFT-D calculations. The crystal structure of DLarginineudprovides interesting contrasts and comparisons to thatudof the enantiomerically pure crystalline phase (L-arginine),udwhich was also determined recently from powder X-rayuddiffraction data.