Jt. Barbas et al., A MECHANISTIC STUDY OF PHOTODECOMPOSITION OF ACENAPHTHYLENE ON A DRY SILICA SURFACE, Journal of photochemistry and photobiology. A, Chemistry, 80(1-3), 1994, pp. 103-111
The photochemistry of acenaphthylene (AC) has been studied on a dry si
lica surface at very low coverages (less than 10% of a monolayer) unde
r aerated conditions. Adsorption of AC onto silica surface from cycloh
exane follows a Freundlich adsorption isotherm, demonstrating a range
of weak interactions between AC and the surface active sites. Photolys
is of AC at the solid-air interface led to the formation of photo-oxid
ation products formed via the addition of singlet molecular oxygen to
ground-state AC, and photodimers (cis and trans). The oxidation produc
ts include 1,2-acenaphthenedione (1), 2-hydroxy-1-acenaphthenone (2),
1,8-naphthalenedicarboxaldehyde (3) and 1,8-naphthalic anhydride (4).
The yield of dimers increases as the surface coverage is raised. Both
the excited singlet state and the excited triplet state of AC are invo
lved in the observed dimerization on the surface.