Organic photochemical storage of solar energy. Progress report, February 1, 1979-January 31, 1980

Technical Report · Fri Feb 01 04:00:00 EST 1980

DOI:https://doi.org/10.2172/5654397· OSTI ID:5654397

Jones, G II

Study of valence isomerization of organic compounds has focused on two mechanisms of photosensitization involving either electron donor-acceptor interaction or energy transfer. The quenching of fluorescent sensitizers by isomerizable substrates results in the formation of excited complexes. These sensitizer-substrate pairs are highly polarized, leading to changes in bond order for the substrates. For several substrates such as quadricyclene, hexamethyldewarbenzene, and a nonbornadiene derivative, this perturbation results in efficient valence isomerization. Isomerization observed on irradiation of charge transfer complexes of isomerizable substrates is consistent with a similar exciplex - template mechanism. The energy transfer mechanism of photosensitization has been studied by measuring the temperature dependence of quantum yield for isomerization of dimethyl norbornadiene-2,3-dicarboxylate sensitized by benzanthrone. From temperature and quencher concentration profiles quenching constants have been obtained which are consistent with an endoergic triplet energy transfer mechanism. The thermal upconversion of the low energy triplet of benzanthrone results in a threefold increase in isomerization quantum yield over a 90/sup 0/ temperature range.

• Research Organization: Boston Univ., MA (USA). Dept. of Chemistry
• DOE Contract Number: EG-77-S-02-4380
• OSTI ID: 5654397
• Report Number(s): COO-4380-3
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140505* -- Solar Energy Conversion-- Photochemical
Photobiological
& Thermochemical Conversion-- (1980-)
ALKENES
AROMATICS
CHARGE TRANSPORT
CHEMICAL REACTIONS
CHEMISTRY
CYCLOALKENES
ENERGY
ENERGY SOURCES
ENERGY STORAGE
ENERGY TRANSFER
HYDROCARBONS
ISOMERIZATION
NORBORNADIENE
ORGANIC COMPOUNDS
PHOTOCHEMICAL ENERGY STORAGE
PHOTOCHEMISTRY
QUADRICYCLENE
REAGENTS
RENEWABLE ENERGY SOURCES
RESEARCH PROGRAMS
SENSITIZERS
SOLAR ENERGY
STORAGE
SUBSTRATES
TEMPERATURE DEPENDENCE
TOLUENE