Crystal Structure of D-Valine at the Temperature of 293, 270, 223 and 173K
The crystal structure of D-valine has been determined by Mo-Kα (λ = 0.71073 A) X-ray diffraction method for the first time. It crystallizes in monoclinic, space group P21 (Z = 4) with a = 9.6728(5), b = 5.2722(3), c = 12.0425(8) A, β = 90.750(2)° at 293 K. The asymmetric unit contains two crystallographically independent molecules — A (trans form) and B (gauche I form). They are rotational isomers with two kinds of conformations about the Cα -Cβ bond. The results of measurements of crystal structure at 293, 270, 223 and 173 K show a little change in bond lengths and geometries as a function of temperature. No evidence was obtained for the existence of configuration transformation from D- to L-valine.
作 者： WANG Wen-Qing GONG Yan WANG Zhe-Ming YAN Chun-Hua 作者单位： WANG Wen-Qing,GONG Yan(Institute of Applied Chemistry, College of Chemistry, Peking University, Beijing 100871, China)WANG Zhe-Ming,YAN Chun-Hua(State Key Laboratory of Rare Earth Materials, Peking University, Beijing 100871, China)
刊 名： 结构化学 ISTIC SCI PKU 英文刊名： CHINESE JOURNAL OF STRUCTURAL CHEMISTRY 年，卷(期)： 2003 22(5) 分类号： O641 关键词： D-valine X-ray diffraction crystal structure low temperature