The S⋯N noncovalent interaction: Comparison with hydrogen and halogen bonds

► Strong attractive force directly between S and N atoms. ► S⋯N structure is global minimum for X = F, with binding energy 8 kcal/mol. ► FS⋯N stronger force than NH⋯F or SH⋯N H-bonds. ► Slightly weaker XS⋯N for X = Cl or Br, but still comparable to H-bonds. ► XS⋯N stronger than SX⋯N halogen bonds.