Numéro
J. Phys. Colloques
Volume 46, Numéro C7, Octobre 1985
Fifth International Conference on Dynamical Processes in the Excited States of Solids / Dynamique des Etats Excités dans les Solides
Page(s) C7-371 - C7-376
DOI https://doi.org/10.1051/jphyscol:1985766
Fifth International Conference on Dynamical Processes in the Excited States of Solids / Dynamique des Etats Excités dans les Solides

J. Phys. Colloques 46 (1985) C7-371-C7-376

DOI: 10.1051/jphyscol:1985766

SUBPICOSECOND SPECTROSCOPIC STUDIES OF SINGLET EXCITON FUSION IN MOLECULAR SOLIDS

B.I. Greene et R.R. Millard

AT&T Bell Laboratories, Murray Hill, New Jersey 07974, U.S.A.


Abstract
The first kinetic data displaying a time-dependent (t-1/2) singlet exciton annihilation rate has been observed. Subpicosecond optical excitation of polycrystalline thin-film samples of β-hydrogen phthalocyanine resulted in excitonic saturation of the crystal lattice. The initial exciton decay yields the only unambiguous measurement of a characteristic annihilation interaction rate for molecular excitons on adjacent lattice sites. Spectroscopic evidence suggests that fusion events produce vibrationally athermal ground state molecules.