Dependence of the activation energy of rhodamine 6G phototransformation into an irreversible photoproduct on the excitation wavelength

Journal Article · Thu Dec 01 04:00:00 EST 1994 · Optics and Spectroscopy

OSTI ID:135622

Aristov, A V ^[1]

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1. Vavilov State Optical Institute, St. Petersburg (Russian Federation)

The results of our previous studies of the quantum yield {Phi}{sub ip} of irreversible phototransformations in rhodamines in deoxygenated solutions are presented along with the results of a quantum-chemical analysis of the dipole-dipole electronic transitions between different molecular orbitals in the 15000-38000 cm{sup -1} spectral region. A combined analysis of these results gives insight into the features of the singlet-singlet absorption spectrum of xanthene dyes in a broad spectral region from 15000 to 38000 cm{sup -1} and explains a considerable difference in values of {Phi}{sub ip} upon excitations into the isoenergetic states in different parts of the absorption spectrum. The relation between the threshold activation energy of the photodestruction of molecules and molecular orbitals involved in the electronic transitions induced by absorption of photons in different spectral regions is found. 10 refs., 1 fig.

• OSTI ID: 135622
• Journal Information: Optics and Spectroscopy, Journal Name: Optics and Spectroscopy Journal Issue: 6 Vol. 77; ISSN 0030-400X; ISSN OPSUA3
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
ACTIVATION ENERGY
EXCITATION
IRREVERSIBLE PROCESSES
PHOTOCHEMICAL REACTIONS
RHODAMINES