Characterization of chalcogen bonding interactions via an in-depth conceptual quantum chemical analysis

摘要: The chalcogen bond has been acknowledged as an influential noncovalent interaction (NCI) between electron-deficient (donor) and a Lewis base (acceptor). This work explores the main features of bonding through large-scale computational study on series donors acceptors spanning wide range in strength character this type bond: (benzo)chalcogenadiazoles (with Ch = Te/Se/S) versus halides neutral bases with O, N, C donor atoms. We start from Pearson's hard soft acids (HSAB) principle, where nature is quantified molecular electrostatic potential Fukui function. σ-holes are more pronounced when going down periodic table their directionality matches structural orientation complexes. functions point toward n→σ*-type interaction. initial conjectures further scrutinized using quantum mechanical methods, mostly relating to systems' electron density. A Ziegler-Rauk energy decomposition analysis shows that electrostatics plays distinctly larger role for than hard, uncharged acceptors, associated softness matching within HSAB principle. natural orbital chemical valence confirms n→σ* donation mechanism. Finally, density local at critical theory atoms molecules position spikes reduced gradient plot NCI situate same strong hydrogen bonds. © 2017 Wiley Periodicals, Inc.