NMR 中的磁化率测量：2. NMR 溶剂的磁化率及其化学位移。

Magnetic susceptibility measurement by NMR: 2. The magnetic susceptibility of NMR solvents and their chemical shifts.

机构信息

Institute of Chemistry, The Hebrew University of Jerusalem, Edmond Y. Safra Campus, Jerusalem 9190401, Israel.

出版信息

J Magn Reson. 2022 Feb;335:107105. doi: 10.1016/j.jmr.2021.107105. Epub 2021 Nov 8.

DOI:10.1016/j.jmr.2021.107105

Abstract

Most routine H NMR spectroscopy references the chemical shift of TMS to zero. However, its chemical shift varies with solvent and environmental conditions. Chemical shifts and magnetic susceptibilities of TMS and several NMR solvents are accurately measured over a range of temperatures. Methods for improving the measurements of chemical shifts and magnetic susceptibilities are developed and demonstrated. This makes it possible to compare chemical shifts of compounds between solvents, improving the accuracy of solvent effect measurements. The effects of polarizability and aromaticity on the chemical shift of TMS are shown. The molar magnetic susceptibilities of the deuterated solvents are similar to those of the regular protiated solvents.

摘要

大多数常规 1H NMR 光谱学将 TMS 的化学位移参考为零。然而，它的化学位移随溶剂和环境条件而变化。TMS 和几种 NMR 溶剂的化学位移和磁化率在一系列温度下得到了精确测量。开发并证明了改进化学位移和磁化率测量的方法。这使得可以在溶剂之间比较化合物的化学位移，从而提高溶剂效应测量的准确性。显示了极化率和芳香性对 TMS 化学位移的影响。氘代溶剂的摩尔磁化率与常规质子化溶剂的磁化率相似。