基于数值计算模拟的仿真核磁共振波谱仪开发

核磁共振(NMR)波谱是研究有机分子结构的重要工具之一,其设备昂贵、仪器数量有限、科研机时安排紧凑、教学实验机时有限;若学生的NMR理论和实验基础较为薄弱,则易发生误操作损坏设备或降低设备性能;另外,NMR实验涉及流程较多、教学耗时较长.因此,针对学生的NMR实验教学难以广泛开展.为将虚拟技术更好地用于辅助NMR实验教学,本文基于数值模拟仿真技术,开发了具备真实NMR波谱仪基本功能的仿真NMR波谱仪——VMRS1.0软件.VMRS1.0软件可实现真实NMR实验须进行的调谐匹配、匀场、锁场、射频脉冲调节、原始数据采集等操作步骤,以及快速傅里叶变换、相位校正、自动寻峰、积分、测距、化学位移校正等基本数据处理功能;除简单的1D 1H和13C NMR波谱采集和数据处理外,还可模拟去偶、DEPT、HSQC等相对复杂的实验;另外,该软件可自行虚拟编辑1H或13C NMR实验样品.VMRS1.0软件摆脱硬件条件的限制,实现了与真实NMR实验类似的教学效果,可以让学生通过反复操作调试,更充分地掌握NMR基本原理和实验技能,再配合在真实NMR谱仪上的少量实际操作,可达到更加令人满意的实验教学效果.

A Virtual NMR Spectrometer Based on Numerical Computational Simulations

Nuclear magnetic resonance (NMR) spectroscopy is an important tool for studying the structures of molecules and materials. Mainly due to their high costs, the NMR spectrometers are often not available for teaching experiments. Teaching NMR experiments cannot be performed routinely and effectively also because that the students are not able to understand the principles underlying the operational steps without proper and adequate training. In this work, a virtual NMR spectrometer (VMRS1.0) for teaching experiments, which is based on numerical computational simulation technology and can be operated like a real spectrometer, is presented. With the VMRS1.0, the students can perform basic NMR experiments, including tuning, shimming, field lock, power adjustment for radio frequency, selecting samples, acquiring data, fast Fourier transform and spectrum processing (i.e., phase correction, integration, chemical shift correction, auto peak finding and J-coupling constant measurement). In addition to the routine one-dimensional NMR experiments, more complicated experiments such as decoupling, DEPT and HMQC can also be performed on the VMRS1.0. With the virtual NMR spectrometer developed, the students can practice their experimental skills and gain deeper understandings of the underlying principles in a more easy and cost-efficient way.