Preparation and structure of Q-state lead sulfide monolayers in metastable stearic acid Langmuir-Blodgett films

Monolayers of Q-state PbS were prepared by exposure of Langmuir-Blodgett (LB) films of lead stearate to H 2 S at a pressure of 1 Torr. Its long spacing measured by X-ray diffraction is 50.5±0.2 A which is just the same with that of lead stearate LB films. It was determined by X-ray diffraction and IR that the hydrocarbon chains are still packed in an orthorhombic unit cell after the reaction. The carboxylic groups yielded by the reaction form a ring structure by hydrogen bonds which controls PbS within a monolayer. A structured UV-visible absorption spectrum of the PbS monolayer was obtained