167989 ⎘
Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light; Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited using photolysis and investigating photolysed fragments Predissociation, e.g. for fluorescence of transient excited radicals