Emission Spectra of Naphthalene Derivatives by Controlled Electron Impact

Abstract

Abstract Naphthalene, 1-methylnaphthalene, 2-methylnaphthalene, 1-naphthol, 1-naphthylamine, 2-chloronaphthalene, 1-bromonaphthalene, 2-bromonaphthalene, and tetralin were excited in a very low pressure by controlled electron beam of 150–400 eV. The molecules, except those with a halogen atom, revealed an intense emission band similar to fluorescence. The band was assigned to the transition from their lowest-excited singlet state to their ground state. It was concluded that the most important process of photoemission is the excitation into a higher excited state in the primary collision and the subsequent non-radiative transfer to the lowest-excited state. The molecules showed photoemission of such excited fragments as H, CH, C2, C4H2+, CN, NH, OH, CO, CO+, HCL+, and HBr+. A two-electron process by way of an intermediate was found to be important for the formation of such fragments as CN from naphthylamine.