Photophysics and Photochemistry of Pentacarbonylpyridino-tungsten(O) Complexes Which Luminesce in Fluid Solution.
Abstract
Luminescence data are reported for W(CO)5L complexes, where L = 4-acetylpyridine, 4-benzoylpyridine, 4-cyanopyridine and 4-formylpyridine, as solids, and in fluid solution. Photosubstitution quantum yields (for the dissociation of L) have been recorded for these W(CO)5L complexes in several solvents using various irradiation wavelengths. Apparent activation energies for the W(CO)5L complexes in several solvents have been measured from the temperature dependencies of the emission and photoreactivity processes. Quenching of the emission and photoreactivity processes are reported for several quenchers; the results are used to bracket the energies of the emitting state for each complex. Two low-lying metal to ligand change-transfer excited states are implicated in the radiative decay process. Possible excited state schemes for these W(CO)5L complexes are discussed in accordance with the experimental observations. Excited state absorption and primary photoproduct spectra have been recorded for the W(CO)5L complexes in methylcyclohexane and benzene by monitoring techniques. A common photoproduct is inferred, its spectrum being close to that of W(CO)5S, where S denotes solvent, following pulse laser photolysis of W(CO)6 as previously reported by us. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 05, 1981
- Accession Number
- ADA102876
Entities
People
- Alistair J. Lees
- Arthur W. Adamson
Organizations
- University of Southern California