Makulski Włodzimierz, Jackowski Karol
Laboratory of NMR Spectroscopy, Faculty of Chemistry, Warsaw University, Pasteura 1, 02-093 Warszawa, Poland.
Laboratory of NMR Spectroscopy, Faculty of Chemistry, Warsaw University, Pasteura 1, 02-093 Warszawa, Poland.
J Magn Reson. 2020 Apr;313:106716. doi: 10.1016/j.jmr.2020.106716. Epub 2020 Mar 23.
Tetramethylsilane (TMS) is well-known as a reference standard of H, C and Si NMR chemical shifts. In the present study, we have observed TMS molecules in gaseous and liquid solutions. In the gas phase, the shielding parameters of TMS are monitored as the functions of density when xenon and krypton are applied as the buffer gases. It permits the evaluation of shielding in an isolated TMS molecule which is determined from the measurements of frequency and available nuclear magnetic moments. Having the shielding constants of an isolated TMS molecule, it is possible to proceed with the evaluation of H, C and Si TMS shielding in liquid state, which is extremely useful for the complete referencing of NMR spectra for protons, carbon-13 and silicon-29 nuclei. Consequently, the readings of chemical shifts and shielding parameters can be practically performed in the same experiment.
四甲基硅烷（TMS）作为氢、碳和硅核磁共振化学位移的参考标准而广为人知。在本研究中，我们观察了气态和液态溶液中的TMS分子。在气相中，当使用氙气和氪气作为缓冲气体时，监测TMS的屏蔽参数随密度的变化。这使得能够评估孤立TMS分子中的屏蔽情况，该屏蔽情况由频率测量和可用核磁矩确定。有了孤立TMS分子的屏蔽常数，就可以进而评估液态下氢、碳和硅的TMS屏蔽，这对于质子、碳-13和硅-29核的核磁共振谱的完整参照极为有用。因此，化学位移和屏蔽参数的读数实际上可以在同一实验中进行。
