Faculty of Chemistry, Adam Mickiewicz University, Poznań, Poland.
Phys Chem Chem Phys. 2011 Sep 14;13(34):15428-31. doi: 10.1039/c1cp21087d. Epub 2011 Jul 27.
Pressure of 1.14(3) GPa leads to the crystallization of a new β phase of pyrrolidine, where every second molecule pseudorotates to the CH(2)-off envelope conformation, energetically less favored than the NH-off envelope. The β phase is triclinic, space group P ̅1, but it is isostructural with monoclinic phase α, where all molecules are in the N-off envelope conformation. The energy associated with the pseudorotation constitutes only about 5% of the total energy change. The energetically unfavorable axial N-H position is retained.
压力为 1.14(3)GPa 导致吡咯烷的新β相结晶，其中每第二个分子伪旋转到 CH(2)-off 信封构象，其能量不如 NH-off 信封构象有利。β相是三斜晶系，空间群 P ̅1，但与单斜晶系 α 是同构的，其中所有分子都处于 N-off 信封构象。与伪旋转相关的能量仅占总能量变化的约 5%。保留了能量不利的轴向 N-H 位置。
