Halogen Bonding or Hydrogen Bonding between 2,2,6,6-Tetramethyl-piperidine-noxyl Radical and Trihalomethanes CHX₃ (X=Cl, Br, I)

The halogen and hydrogen bonding complexes between 2,2,6,6-tetramethylpiperidine-noxyl and trihalomethanes (CHX₃, X=Cl, Br, I) are simulated by computational quantum chem-istry. The molecular electrostatic potentials, geometrical parameters and interaction energy of halogen and hydrogen bonding complexes combined with natural bond orbital analysis are obtained. The results indicate that both halogen and hydrogen bonding interactions obey the order Cl