The crystal structure of DL-ornithine hydrobromide

Abstract

The crystal structure of DL-ornithine hydrobromide NH₃(CH₂)₃.CH(NH⁺₃).COO^-HBr has been deter-mined using three-dimensional visual intensity data obtained with Cu Kα radiation. The crystal belongs to the monoclinic system with cell dimensions a=9.388; b=7.901; c=11.663Å and β=109°50'. The space group is P2₁/c. The structure has been refined using the full matrix least-square method. Final R value is 7.3% for the observed data. All the hydrogen atoms have been located from a difference Fourier synthesis. The standard deviation for the positions of the non-hydrogen atoms is about 0.008Å. All bond lengths and angles are found to be normal. Both nitrogen atoms are protonated and the carboxyl group exists in the ionic form. The conformation and other aspects of the molecule are discussed.