The fluorescence behaviour of poly(methacrylates) with benzanilide side gro
ups and that of related monomer model compounds are compared in solution, c
rystalline state and as spin-coated films. The fluorescence of benzanilide
is characterized by three competitive radiative processes. In addition to t
he normal fluorescence Fl at 345 nm, a superposition of proton transfer (PT
) fluorescence and intramolecular charge transfer (ICT) fluorescence is obs
erved, characterized by a large Stokes shift. The emission of the crystalli
ne monomers, solid polymers and spin-coated films is caused by intermolecul
ar interactions between the benzanilide moieties in form of hydrogen bonds
and by an intramolecular charge transfer process. Because of the high effic
iency of these interactions, the fluorescence intensity of the normal fluor
escence is strongly decreased in solid states and glassy films. The deactiv
ation behaviour of the polymers is investigated in dependence on the matrix
properties varied by the temperature. Moreover, it is demonstrated that th
e intermolecular interactions of the benzanilides are strongly influenced b
y changes in its intramolecular properties like the modification of the par
a-substitution of the benzanilide moieties. Photochemical deactivation proc
esses affect neither the photophysical behaviour of the benzanilides in sol
ution nor in the solid state. (C) 2000 Elsevier Science B.V. All rights res
erved.