The N⋯I halogen bond in substituted pyridines as viewed by the source function and delocalization indices

• Published in: Chemical physics letters Vol. 601; pp. 144 - 148
• Main Authors: Bartashevich, Ekaterina V., Troitskaya, Elena A., Tsirelson, Vladimir G.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 09.05.2014
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/j.cplett.2014.04.004

•Delocalization indices for halogen bond correlate with atomic sources.•The major contribution to the electron density of N⋯I interaction goes from iodine.•Delocalization indices of halogen bond are correlated with the basicity pKBI2. The features of electron density in the complexes of substituted pyridines have been studied with a special attention to the N⋯I halogen bonding. The source function indicates that the major contribution to the electron density at the bond critical point of N⋯I interaction goes from the basin of iodine atom. The delocalization indices for halogen bond N⋯I quantitatively correlate with the sum of atomic sources of iodine and nitrogen. This finding allows estimating the delocalization indices directly from the electron density. The delocalization indices of halogen bond are well correlated with the basicity pKBI2 according to the diiodine basicity scale.