The Badger-Bauer rule revisited: correlation of proper blue frequency shifts in the OC hydrogen acceptor with morphed hydrogen bond dissociation energies in OC-HX (X = F, Cl, Br, I, CN, CCH).

Potential morphing has been applied to the investigation of proper blue frequency shifts, Δν0 in CO, the hydrogen acceptor complexing in the hydrogen bonded series OC–HX (X= F, Cl, Br, I, CN, CCH). Linear correlations of morphed hydrogen bonded ground dissociation energies D0 with experimentally determined Δν0 free from matrix and solvent effects demonstrate consistency with original tenets of the Badger–Bauer rule (J. Chem. Phys. 1937, 5, 839–51). A model is developed that provides a basis for explaining the observed linear correlations in the range of systems studied. Furthermore, the generated calibration curve enables prediction of dissociation energies for other related but different complexes. The latter include D0 for H2O–CO, H2S-CO, and CH3OH–CO which are predicted by interpolation and found to be 355(13), 171(11), and 377(14) cm–1 respectively from available experimentally determined proton acceptor shifts. Results from this study will also be discussed in relation to investigations in which CO h...