The structural deformation induced by intense laser field of liquid nitrobenzene(NB) molecule,a typical molecule with restricting internal rotation,is tracked by time- and frequency-resolved coherent anti-Stokes.Ram...The structural deformation induced by intense laser field of liquid nitrobenzene(NB) molecule,a typical molecule with restricting internal rotation,is tracked by time- and frequency-resolved coherent anti-Stokes.Raman spectroscopy(CARS) technique with an intense pump laser.The CARS spectra of liquid NB show that the NO2 torsional mode couples with the NO2 symmetric stretching mode,and the NB molecule undergoes ultrafast structural deformation with a relaxation time of 265 fs.The frequency of NO2 torsional mode in liquid NB(42 cm-1) at room temperature is found from the sum and difference combination bands involving the NO2 symmetric stretching mode and torsional mode in time- and frequency-resolved CARS spectra.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.21173063 and 21203047)the Foundation of Heilongjiang Bayi Agricultural University,China(Grant No.XZR2014-16)+1 种基金NSAF(Grant No.U1330106)the Special Research Project of National Key Laboratory of Shock Wave and Detonation Physics,Institute of Fluid Physics,China Academy of Engineering Physics(Grant No.2012-S-07)
文摘The structural deformation induced by intense laser field of liquid nitrobenzene(NB) molecule,a typical molecule with restricting internal rotation,is tracked by time- and frequency-resolved coherent anti-Stokes.Raman spectroscopy(CARS) technique with an intense pump laser.The CARS spectra of liquid NB show that the NO2 torsional mode couples with the NO2 symmetric stretching mode,and the NB molecule undergoes ultrafast structural deformation with a relaxation time of 265 fs.The frequency of NO2 torsional mode in liquid NB(42 cm-1) at room temperature is found from the sum and difference combination bands involving the NO2 symmetric stretching mode and torsional mode in time- and frequency-resolved CARS spectra.