PCARS measurement of nucleiosides vibrational structure

The polarization sensitive CARS (coherent anti-stokes Raman spectroscopy) method is used for the direct spectroscopic investigating of the vibration of double bonds in nucleiosides. The nonresonant background in CARS has been effectively suppressed and the vibration mode of these double bonds can be clearly resolved. The spectral features are discussed in terms of the characteristic group frequency and analogies with spectra of molecules with related structures. These spectral feature may be of use for studying biomolecules of unknown composition.