Abstract: Ab initio calculations of the ¹⁵N chemical shifts are reported for two Schiff bases. The calculations were performed with the gauge invariant atomic orbital (GIAO) quantum chemical approach. Optimized geometrical parameters were used. The predicted results successfully reproduce the observed ¹⁵N shielding values for the two compounds taken in the solid state. It is demonstrated that the calculation reasonably confirms the ¹⁵N chemical shielding behavior due to the formation of an intramolecular hydrogen bond.

Key words: Ab initio method, ¹⁵N chemical shift, GIAO approach, Schiff base