Complex hydrogen bonded cations

Spectroscopic evidence is presented for the occurrence of a number of asymmetric complex cations, of formula (B 1 B 2 ) + where B 1 and B 2 differ, and may be pyridine, 4-methylpyridine, 2,6- and 3,5-dimethylpyridine, 2,4,6-trimethyl-pyridine, 2-fluoropyridine, 3-chloropyridine or quinoline. In the H-bridged cations, the NH stretching band v s is doubled, the ratio of the intensities of the components varying regularly with AΔp K a of the component bases. In the D-bridged cations, only a single v s band is observed. All features in the spectra evolve continuously from those of the symmetric cations (B 1 = B 2 ).