Effects of hydrogen bond formation on vibrations of pyridine, pyrazine, pyrimidine, and pyridazine
Abstract
Vibrational frequency shifts of pyridine, pyrazine, pyrimidine, and pyridazine have been studied in several hydrogen donor solvents, H 2O, D 2O, CH 3OH, C 2H 5OH, and CHCl 3. Shifts to higher frequencies of almost all the vibrations of these molecules have been observed. In particular, new bands, which clearly arise from hydrogen bonded species, have been detected for skeletal vibrations, ν1, ν6 a, and ν8 a (nomenclature after Lord et al.), in pyridine and pyrimidine. From the shifts to higher frequencies, it is concluded that considerable changes of electron distribution which strengthen the chemical bonds in these molecules take place when they participate in hydrogen bonds.
- Publication:
-
Journal of Molecular Spectroscopy
- Pub Date:
- 1966
- DOI:
- 10.1016/0022-2852(66)90139-1
- Bibcode:
- 1966JMoSp..21..217T