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利用单晶的中子衍射研究295K和60K时丙氨酸对映体的结构特征以及由D到L构型转变的可能性.中子衍射数据揭示了变温过程中产生的晶格扭曲和NH3+的扭转.通过分析宇称破缺能差EPV随二面角及扭角的变化,肯定了D-丙氨酸能量高于L-丙氨酸的结论.降温过程中D-和L-丙氨酸的弱氢键的行为的差异表明,可能是由于电弱相互作用宇称不守恒所引起.丙氨酸中子结构再次证实Cα-H…O氢键的存在.然而,比较295K和60K(高于和低于丙氨酸相变温度250K)的中子衍射结构数据,表明并没有发生D型到L型的构型转化,这意味着Salam相变不是传统意义的结构相变.
The structural characteristics of the alanine enantiomer at 295K and 60K, as well as the possibility of transition from D to L configuration, were investigated by neutron diffraction of single crystal.The neutron diffraction data revealed that lattice distortion and NH3 + Reversed.According to the analysis of EPV with dihedral angle and twist angle, the conclusion is that D-alanine energy is higher than L-alanine.D-and L-alanine The difference in the behavior of the weak hydrogen bonds suggests that this may be due to the nonconservation of the parity of the weak interaction.The alanine neutron structure confirms the presence of Cα-H ... O hydrogen bonds again.However, comparing the 295K and 60K (high Neutron diffraction structure data at and below the alanine phase transition temperature of 250K indicate that no D-type to L-type configuration transitions occur, meaning that the Salam phase transition is not a structural phase change in the traditional sense.