Steacie Institute for Molecular Sciences, National Research Council, Ottawa, Ontario, Canada.
J Phys Chem A. 2011 Feb 10;115(5):747-52. doi: 10.1021/jp111531e. Epub 2010 Dec 21.
A combination of density functional and optimal control theory has been used to generate amplitude- and phase-modulated excitation pulses tailored specifically for the (33)S nuclei in taurine, based on one of several reported crystal structures. The pulses resulted in significant signal enhancement (stemming from population transfer from the satellite transitions) without the need for any experimental optimization. This allowed an accurate determination of the (33)S NMR interaction parameters at natural abundance and at a moderate magnetic field strength (11.7 T). The (33)S NMR parameters, along with those measured from (14)N using frequency-swept pulses, were then used to assess the accuracy of various proposed crystal structures.
采用密度泛函和最优控制理论相结合的方法，根据几种已报道的晶体结构中的一种，为牛磺酸中的（33）S 核生成了专门定制的幅度和相位调制激发脉冲。这些脉冲导致了显著的信号增强（源自从卫星跃迁的种群转移），而无需任何实验优化。这使得能够在自然丰度和中等磁场强度（11.7 T）下准确确定（33）S NMR 相互作用参数。然后，将（33）S NMR 参数与使用频率扫描脉冲从（14）N 测量的参数一起用于评估各种提出的晶体结构的准确性。
