Abstract

Using the femtosecond optical-heterodyne detected, Raman-induced Kerr effect spectroscopic technique¹,² (fs-OHD-RIKES), we have characterized the full spectrum of the intermolecular vibrational and diffusive dynamics for a series of five amides. The OHD-RIKES birefringence transients of the neat liquids formamide (FA), N-methylformamide (NMF), N,N-dimethylformamide (DMF), N-methylacetamide (NMA), and N-methyl-propionamide (NMP) were measured in at temperatures in the range 290-370 K. Because we have used 50 fs, transform-limited pulses to perform the experiments, we impulsively excite all of the intermolecular motions in the 0 to 400 cm^-1 range. Use of optical-heterodyne detection permits observation of a response linear in the molecular response; thus we can analyze the data in both the time and frequency domains by Fourier-transform inversion.²

© 1996 Optical Society of America