Halogen bond-driven azo–hydrazone tautomerisation: a computational study

CONTEXT: ), halogen bonding can invert the tautomeric preference. External factors such as temperature affect the halogen bonding strength and thereby the tautomeric equilibrium, suggesting that these halogen-bonded systems may offer a tunable platform for sensing applications. METHODS: The Gaussian 16 program was used for geometry optimisations, interaction energy calculations, and to generate the wavefunctions. All calculations were performed using the M06-2X/DGDZVP density functional theory method. The counterpoise correction method by Boys and Bernardi was used to correct for the basis set superposition error. The AIMAll program was used to perform the interacting quantum atoms analyses of the wavefunctions.