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A few-monolayer zwitterionic, non-centrosymmetric Langmuir-Blodgett film has been sandwiched between two electrodes, one of which is transparent. Curves of dark current density as a function of applied bias were observed to exhibit rectifier-like behaviour and to follow closely the dependences measured from junctions using two metallic electrodes. The transparent indium tin oxide (ITO) electrode discussed here permitted illumination of the organic film during electrical characterisation and it was observed that the electrical behaviour was altered from the dark state. Illumination has the effect of generating a photocurrent even when no bias is applied to the electrodes; in addition, the junction conductance was increased. © 1997 John Wiley & Sons, Ltd.

In this study, surface plasmon resonance studies of Langmuir-Blodgett multilayers have been used to characterize an optically highly absorbing zwitterionic material which would be difficult to otherwise analyse. By fitting reflectivity data with Fresnel theory for a range of wavelengths it has been possible to obtain the real and imaginary parts of the assumed-isotropic dielectric optical permittivity over the visible part of the spectrum. These results show an asymmetric resonance peak which may be interpreted as being a composite of two resonances, one associated with an intermolecular dipole transition and one with an intramolecular dipole.

The influence on the near critical angle reflectivity of a thin deposited on the face of a glass prism is used to optically characterize a zwitterion Langmuir-Blodgett film.