  In recent years it became possible to align molecules in free space using
ultrashort laser pulses. Here we explore two schemes for controlling
molecule-surface scattering process, which are based on the laser-induced
molecular alignment. In the first scheme, a single ultrashort non-resonant
laser pulse is applied to a molecular beam hitting the surface. This pulse
modifies the angular distribution of the incident molecules, and causes the
scattered molecules to rotate with a preferred sense of rotation (clockwise or
counter-clockwise). In the second scheme, two properly delayed laser pulses are
applied to a molecular beam composed of two chemically close molecular species
(isotopes, or nuclear spin isomers). As the result of the double pulse
excitation, these species are selectively scattered to different angles after
the collision with the surface. These effects may provide new means for the
analysis and separation of molecular mixtures.
