CRYSTAL STRUCTURE OF L-ARGININE HYDROCHLORIDE

L-arginine hydrochloride, C6H14N4O2 • HCl, crystallizes in space group P2i with 4 molecules in the unit cell of dimensions α = 5.33 Å, b = 9.46 A, c = 20.07 Å and β = 90° 30'. The structure was determined by the heavy-atom method and refined by three-dimensional least-squares computations to R = 0.091. The two crystallographically independent molecules differ only insignificantly. Bond lengths and bond angles are normal. The arginino molecules occur as zwitterions, with the amino groups and the guanidyl groups each accepting a proton from the acid groups and the hydrochloric acid. All available hydrogen atoms participate in the formation of intermolecular bonds. © 1969, Walter de Gruyter. All rights reserved.