The Effect of Chemical Exchange on Energy and Phase Relaxation-Processes in Nuclear Magnetic Resonance Spectroscopy

化学交换反应动力学和平衡性质的研究，用核磁共振和同位素取代方法研究了离子溶液中的原子排列和局域排列，考察了化学交换对离子溶液中的原子排列的影响。通过使用时间演化的耦合表达式的一般解，计算了核磁共振纵向磁化恢复曲线和核磁共振谱中的形状位置A和B的纵向磁化强度。(1)本文用~（2Al）NME研究了Al_2（SO_4）_3水溶液中[Al（H_2O）_6]^&lt;3+&gt;+ so_2-_<double arrow>[Al（H_2O）_5SO_4]^+ + H_2O的配体交换反应和（2）氯铝酸盐熔体中不同络合物之间的交换反应<double arrow><27>。本文<25><31>应用~（13）Mg和~（13）P核磁共振研究了Mg^&lt;2+&gt;在ATP中与~（13）P结合的两个非桥氧周围的几何构型<bata>以及Mg^&lt;2+&gt;与ATP的相互作用。(3)在ATP + Mg^&lt;2+&gt;水溶液中，ATP结合的Mg^&lt;2+&gt;与第一配位球失去水分子的Mg^&lt;2+&gt;之间可能发生交换反应.本文用中子衍射仪和Li、N同位素替代法研究了LiAlCl_4和LiNO_3熔体的结构.对它们之间可能的构象以及与Li^+配离子的可能配位进行了说明。

The studies on the kinetic and equilibrium properties of chemical exchangereaction, and local atomic-arrangement in the ionic solutions were carried out by using nuclear magnetic resonance and isotopic substitution methods.We have investigated the influence of chemical-exchange on the line-shapes in the NMR longitudinal magnetization recovery curves as well as in the NMR spectra by using a general solution of the coupled expressions for the time evolution of the longitudinal magnetizations of sites A and B. (1) The ligand exchange-reaction in aqueous Al_2(SO_4)_3 solution[Al(H_2O)_6]^<3+>+so^2-_<double arrow> [Al(H_2O)_5SO_4]^+ + H_2O and (2) the exchange-reaction between different complex-species in chloroaluminate melts2Alc1^-_ <double arrow> Al_2C1^-_ + Cl^-was characterized about their kinetic and equilibrium properties by using ^<27>Al NME. The ^<25>Mg and ^<31>P nuclear magnetic resonance was applied to a study of geometry of Mg^<2+> around two non-bridging oxygens binding to <bata>-phosphorus in ATP and interaction of Mg^<2+> with ATP. (3) The exchange reaction in aqueous ATP + Mg^<2+> solution may take place between ATP-bound Mg^<2+> separated from ATP by a water molecule and tightly site-bound Mg^<2+> which loses the water molecule from the first coordination sphere.The structures of molten LiAlCl_4 and LiNO_3 have been investigated by means of neutron diffractometer, using the method of Li and N isotopic substitution. The possible conformation among them as well as the possible coordination by complex ion of Li^+ was illustrated.