Any technique in which a specimen is bombarded with a finely focused @L03459@ beam (diameter less than \(10\ \unicode[Times]{x3BC}\text{m}\)) in the @UT07492@ or @VT07496@ range and the intensity versus @W06659@ function of the Raman radiation is recorded yielding information about vibrational states of the excited substance and therefore also about functional groups and chemical bonding.