Physical Sciences and Mathematics Commons^™

Comparison Of Ch∙∙O, Sh∙∙O, Chalcogen, And Tetrel Bonds Formed By Neutral And Cationic Sulfur-Containing Compounds, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The ability of neutral and charged S-compounds to form different sorts of noncovalent bonds is examined by ab initio calculations. Neutrals are represented by CH3SH and fluoro substituted FSCH3; cations are (CH3)3S+, CH3SH2+, and FHSCH3+. Each is paired with N-methylacetamide (NMA) whose O atom serves as common electron donor. Charged species engage in much stronger noncovalent bonds than do the neutral molecules, by as much as an order of magnitude. The strongest noncovalent bond for any system is a O∙∙SF chalcogen bond wherein the O lies directly opposite a S-F covalent bond, amounting to as much as 39 kcal/mol. Second …