Surface Plasmon Study of Monolayer-Bilayer Transition in Poly-4-BCMU and Poly-3-BCMU Polydiacetylene Langmuir-Blodgett Films

摘要

Surface plasmon wave spectroscopy was successfully used to study the monolayer-bilayer transition in poly-4-BCMU and poly-3-BCMU polydiacetylene Langmuir-Blodgett films. The linear refractive index and the thickness were obtained for the monolayer yellow and bilayer red forms of poly-4-BCMU. Surface plasmon coupling using resonance enhancement was found to sufficiently enhance the Raman scattering, so Raman spectra of the monolayer films could be obtained with a relatively small laser intensity of a few milliwatts. The differences in the c(doubles bond)c and c(triple bond)c vibrational stretching frequencies of the monolayer yellow and the bilayer films were observed arising from the difference in the effective conjugation of the two forms. Electrochemistry; Plasmon waves; Reprints. (jhd)