Discrete electronic-vibrational fluorescence spectra in the low-pressure phenanthrene and naphthacene vapors

Journal Article · Wed Oct 01 04:00:00 EDT 1986 · J. Appl. Spectrosc. (Engl. Transl.); (United States)

OSTI ID:6848115

Mirumyants, S O; Kozlov, V K; Vandyukov, E A

In recent years considerable attention has been paid to developing methods for analysis and control of air pollutants. In this work the results of the study on quasiline fluorescence spectra for phenathrene and naphthacene in the gas phase are presented. Despite the fact that phenanthrene is a stereoisomer of anthracene, the shapes and intensities of their absorption and fluorescence spectra are markedly different. The oscillator strength of the first electronic transition in anthracene vapors is 50 times larger than that for the phenanthrene vapor (0.1 and 0.002, respectively). Therefore, the studies of the quasiline fluorescence spectrum of the phenanthrene vapor required a long exposition period (from 7 to 31 h) during the photographic detection. It is known that phenanthrene exhibits a characteristic quasiline spectrum in the 34584000-A range in frozen solutions. The authors have also investigated the possibility of obtaining structured quasiline vapor spectra for a more complex aromatic compound such as naphthacene which comprises four benzyl rings. In conclusion, the quasiline fluorescence spectra for phenanthrene and naphthacene in the gas phase have been obtained for the first time. In certain experimental conditions, phenanthrene and naphthacene emit wellresolved quasiline spectra which are dependent on the excitation frequency, temperature, and vapor pressure. For both compounds there is a frequency range for quasiline fluorescence excitation for which a shift of the quasiline spectrum occurs if the excitation frequency is changed within that range. Also more accurate values for the frequencies of the O-O electronic transition in phenanthrene and naphthacene have been obtained. Diagrams are included.

• OSTI ID: 6848115
• Journal Information: J. Appl. Spectrosc. (Engl. Transl.); (United States), Journal Name: J. Appl. Spectrosc. (Engl. Transl.); (United States) Vol. 44:4; ISSN JASYA
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
ABSORPTION SPECTRA
AIR POLLUTION ABATEMENT
AIR POLLUTION MONITORING
AROMATICS
CONDENSED AROMATICS
EMISSION SPECTROSCOPY
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXCITATION
EXCITED STATES
FLUIDS
FLUORESCENCE SPECTROSCOPY
FREQUENCY DEPENDENCE
GASES
HYDROCARBONS
ORGANIC COMPOUNDS
PHENANTHRENE
PHYSICAL PROPERTIES
POLLUTION ABATEMENT
SPECTRA
SPECTRAL SHIFT
SPECTROSCOPY
TETRACENE
THERMODYNAMIC PROPERTIES
VAPOR PRESSURE
VAPORS
VIBRATIONAL STATES