Structural aspects of molecular photoionization efficiency in micelles and vesicles as models for solar energy utilization. [N,N,N',N'-tetramethylbenzidine]

Conference · Sat Jan 01 04:00:00 EST 1983

OSTI ID:6942543

Kevan, L

The structural aspects controlling charge separation in molecular photoionization reactions in organized molecular assemblies involving micelles and vesicles are being studied by optical and electron magnetic resonance techniques including the time domain technique of electron spin echo modulation (ESEM). Photoionization of N,N,N',N'-tetramethylbenzidine (TMB) to give the cation radical has been carried out in both liquid and frozen micellar and vesicular solutions. Cation-water interactions have been detected by ESEM analysis and indicate that the cation is localized asymmetrically within these organized molecular assemblies. Stearic acid nitroxide spin probes have also been used to determine that the neutral TMB molecule before photoionization is also localized asymmetrically within such organized molecular assemblies. Electron spin echo detection of laser photogenerated TMB cation in liquid micellar solutions gives a direct measurement of the phase memory magnetic relaxation time which gives additional structural information. The relationship of this structural data to the efficiency of photoionization in these systems is discussed.

• Research Organization: Houston Univ., TX (USA). Dept. of Chemistry
• DOE Contract Number: AS05-80ER10745
• OSTI ID: 6942543
• Report Number(s): CONF-830839-3; ON: DE84011837
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500* -- Photochemistry
AMINES
AROMATICS
CATIONS
CHALCOGENIDES
CHARGED PARTICLES
ELECTRON SPIN RESONANCE
IONIZATION
IONS
MAGNETIC RESONANCE
MICELLAR SYSTEMS
NITROGEN COMPOUNDS
NITROGEN OXIDES
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHOTOIONIZATION
PROBES
RADICALS
RESONANCE
SPIN ECHO