A series of perylene tetracarboxylic diimides and monoimides have been fabricated into Langmuir and Langmuir-Blodgett films. These films have been spectroscopically characterized through UV-visible absorption, steady-state fluorescence, infrared and Raman techniques. Molecular exciton and excimer formation have been observed for these films. The average molecular orientation of the chromophore was deduced through infrared transmission and reflection/absorption techniques. Electronic spectroscopy revealed the nature of the packing of the materials. The role of subphase/molecule and molecule/molecule interactions in the structure of the film were discussed, as well as the role of the imide substitution. These materials were successfully incorporated, as donors, into energy transfer systems with lutetium diphthalocyanine as an acceptor. These monolayers were used to investigate surface enhanced infrared and surface enhanced infrared reflection/absorption. The distance dependence and angle dependence of the enhancement in the infrared was simulated by using the Maxwell-Garnett composite layer model. Source: Dissertation Abstracts International, Volume: 56-11, Section: B, page: 6134. Adviser: Ricardo Aroca. Thesis (Ph.D.)--University of Windsor (Canada), 1995