Assignment of molecular species by experimental and theoretical data bases in supersonic jet spectrometry

Abstract

Imasaka, T., Sakaki, K. and Ishibashi, N. 1989. Assignment of molecular species by experimental and theoretical data bases in supersonic jet spectrometry. Chemometrics and Intelligent Laboratory Systems, 6: 281–289. A chemometric approach is applied to the assignment of chemical species in supersonic jet spectrometry, which is based on the use of a data base constructed either experimentally or theoretically. The experimental data base is reliable for assignment, if standard spectral parameters are known. However, if there are no data for standards or no synthesized standard chemicals, the theoretically-constructed data base may be used. To discuss the reliability of the theoretical approach, the energies of pure electronic transitions are calculated for various aromatic hydrocarbons by using PPP and CNDO/S methods. Correlation between the theoretical and experimental values is fair, standard deviations being 1–3%. Theoretical values for phenol and aniline derivatives are slightly but systematically shifted to shorter wavelengths.