Molecular lens applied to benzene and carbon disulfide molecular beams

A molecular lens of the nonresonant dipole force formed by focusing a nanos econd IR laser pulse has been applied to benzene and CS2 molecular beams. U sing the velocity map imaging technique for molecular ray tracing, characte ristic molecular lens parameters including the focal length (f ), minimum b eam width (W), and distance to the minimum beam width position (D) were det ermined. The laser intensity dependence of the observed lens parameters was in good agreement with theoretical predictions. W was independent of the l aser peak intensity (I-0), whereas f and D varied linearly with 1/I-0. The differences in lens parameters between the molecular species were well corr elated with the polarizability per mass values of the molecules. A high chr omatographic resolution of Rs = 0.84 was achieved between the images of ben zene molecular beams undeflected and deflected by the lens. The possibiliti es for a new type of chromatography are discussed. (C) 2001 American Instit ute of Physics.