LATTICE EFFECTS IN THE SPECTRA OF ANTHRACENE IN NAPHTHALENE AND PHENANTHRENE.

Loading...
Thumbnail Image

Date

1969

Journal Title

Journal ISSN

Volume Title

Publisher

Ohio State University

Research Projects

Organizational Units

Journal Issue

Abstract

We have investigated ($4.2^{\circ}-90^{\circ}$K) the absorption and emission spectra of anthracene in naphthalene at low concentration (approximately $10^{6}:1$) and in phenanthrene at higher concentrations (approximately $10^{4}:1$). The results agree, in general, with published data. However, the bands are better resolved and a more detailed assessment of the lattice participation in the first anthracene singlet transition has been made possible. The participation of optical and acoustic phonons is discussed in some detail. Anthracene in these two hosts does not exhibit the striking dependence of the azulene (naphthalene host) absorption and emission spectra on concentration. (Kazzaz and Zahlan, unpublished). In the azulene case the 0-0 phonon side band's intensity is much greater in concentrated than in very dilute mixed crystals. The distribution of anthracene emission intensity among the $0-0$ and vibronic transitions is different in the phenanthrene and naphthalene hosts. In naphthalene the band system around $0-0+1400 cm^{-1}$ comparable in intensity to the 0-0+phonons system; while in phenanthrene this $0-0+ 1400 cm^{-1}$ system is some ten times stronger than the $0-0$ system. The fluorescence intensity distribution is temperature dependent.

Description

Author Institution: Physics Department, American University of Beirut

Keywords

Citation