Nature and strength of chalcogen–π bonds

作者：Marco Bortoli, Shah Masood Ahmad, Trevor A. Hamlin, F. Matthias Bickelhaupt, Laura Orian · 发表于：Physical Chemistry Chemical Physics · 年份：2018 · DOI：10.1039/c8cp05922e · 被引用次数：38 · 研究领域：Crystallography and molecular interactions、Organic and Molecular Conductors Research、Organometallic Compounds Synthesis and Characterization

Chalcogen-π interactions occur between a covalently bound chalcogen atom that enters into a non-covalent interaction with an unsaturated moiety, a bonding motif found in various structures, such as, proteins. In this work, we have systematically explored and analyzed chalcogen-π interactions in model systems X2DA (with D = O, S, Se, Te; X = halogen; A = acetylene, ethylene and 2-butyne), using relativistic density functional theory (DFT). The nature and trends in stability of the chalcogen-π bonds are analyzed and interpreted in terms of quantitative MO theory in combination with a matching canonical energy decomposition analysis (EDA) scheme. We find that chalcogen-π bonds increase in strength as the X-D electronegativity difference becomes greater. Moreover, 2-butyne was found to participate in the strongest non-covalent interaction due to enhanced orbital interactions.