Referencing of 1H and 13C NMR shielding measurements

Direct measurements of 1H, 2H and 13C NMR shielding are performed for 13 deuterated liquid solvents using an isolated helium-3 atom as the primary reference standard of shielding. It has been possible exploring the absolute resonance frequencies and nuclear magnetic moments of the investigated nuclei. The measured shielding values are verified using appropriate chemical shifts with the accurate values of 1H and 13C shielding in liquid TMS. As shown, all the new 2H shielding parameters of the investigated solvents can be applied as the secondary reference standards of shielding for gases and liquids in usual NMR laboratory practice.