Monolayer formation and Langmuir-Blodgett films of benzimidazole derivatives without alkyl chain

The monolayer formation and morphology of two benzimidazole derivatives, 2- phenylbenzimidazole (PhBz) and 2-(2'-pyridyl)benzimidazole (PyBz), which ha ve no alkyl chains, have been investigated. These compounds can form monola yers on subphases containing concentrate AgNO3. No monolayers are formed on water or subphases containing other ions. Differences are found in the beh aviors of the two compounds owing to the different hydrophilicity of the py ridyl and phenyl rings. Similar iceberg-like domains are observed in both t he monolayers immediately after spread using a Brewster angle microscopy. T he monolayers can be transferred onto solid substrates as X-type LB films. X-ray diffraction shows the regular layer structure of the LB films with lo ng spacings of 1.19 and 1.33 nm for PhBz and PyBz, respectively. (C) 2000 P ublished by Elsevier Science B.V. All rights reserved.