ISSN:
1572-8854
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
,
Physics
Notes:
Abstract A neutron diffraction study of the β-form of L-glutamic acid, C5H9NO4, has been carried out. The structure is orthorhombic: space groupP212121,a= 5·159(5),b= 17·30(2),c= 6·948(7) Å andz = 4. Least-squares refinements based on 803 reflexions led to a final conventionalR value of 0·026, and bond lengths involving hydrogen atoms have been determined with an average precision of 0·004 Å. The molecule is in the zwitterion form, and no intramolecular hydrogen bonds have been found. The hydrogen atom involved in a strong hydrogen bond between two carboxyl groups in adjacent molecules (0 ... 0 distance 2·519(2) Å) is covalently bonded to the carboxyl group belonging to the side chain of the amino acid. This side chain is buckled with Cδ gauche to Cα with respect to the C β —C γ bond. The bond angles involving carbon atoms in the side chain are accordingly strained.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01246639
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