DFT calculations 1 Journal Article 1 anion of N,N‐(naphthalene‐1,8‐diyl)bis(2,2,2‐trifluoracetamide) 1 anions of 1,8‐bis(4‐toluenesulphonamido)naphthalenes 1 deuterium isotope effects on 13C chemical shifts 1 intramolecular hydrogen bonds