A molecular theory of time-resolved sum-frequency generation (SFG) has been developed. The theoretical framework is constructed using the coupled-oscillator model in the adiabatic approximation. This theory can treat not only the vibrational spectroscopy but also vibrational dynamics. An application of this theory is also provided for estimation of the time constants of the intermolecular vibra...

Vibrational properties of graphene nanoribbons are examined with density functional based tight-binding method and non-resonant bond polarization theory. We show that the recently discovered reconstructed zigzag edge can be identified from the emergence of high-energy vibrational mode due to strong triple bonds at the edges. This mode is visible also in the Raman spectrum. Total vibrational den...

Using picosecond time-resolved photoelectron imaging we have studied the intramolecular vibrational energy redistribution (IVR) dynamics that occur following the excitation of the 35 level which lies 2068 cm above the S1 origin in p-difluorobenzene. Our technique, which has superior time resolution to that of earlier studies but retains sufficient energy resolution to identify the behavior of i...

We present new vibrational (infrared) planar laser-induced fluorescence (PLIF) imaging techniques for CO(2) that use a simple, inexpensive, high-pulse-energy transversely excited atmospheric CO(2) laser to saturate a CO(2) absorption transition at 10.6 mum. Strong excitation by use of a CO(2) laser provides increased signal levels at flame temperatures and simplifies image interpretation. Becau...

The loss or gain of vibrational energy in collisions of an NO molecule with the surface of a gold single crystal proceeds by electron transfer. With the advent of new optical pumping and orientation methods, we can now control all molecular degrees of freedom important to this electron-transfer-mediated process, providing the most detailed look yet into the inner workings of an electron-transfe...

Using picosecond time-resolved photoelectron imaging we have studied the intramolecular vibrational energy redistribution (IVR) dynamics that occur following the excitation of the 35 level which lies 2068 cm above the S1 origin in p-difluorobenzene. Our technique, which has superior time resolution to that of earlier studies but retains sufficient energy resolution to identify the behavior of i...

Bioactive molecules are playing essential role in the field of drug discovery and various pharmaceutical applications. Vibrational spectral investigations of the anti-Candida agent ({[(1E)-3-(1H-imidazol-1-yl)-1-phenylpropylidene]amino}oxy)(4-methylphenyl)methanone ((1E)-IPMM) have been recorded and analyzed to understand its structural geometry, interand intra-molecular interactions. The equil...

The experimental observations of vibrational mode- and bond-selective chemistry at the gas-surface interface indicate that energy redistribution within the reaction complex is not statistical on the timescale of reaction. Such behavior is a key prerequisite for efforts to use selective vibrational excitation to control chemistry at the technologically important gas-surface interface. This paper...

The vibrational energy dependence, H and D atom isotope effects, and the mass effects in the energy transfer between rare gas atoms and highly vibrationally excited naphthalene in the triplet state were investigated using crossed-beam/time-sliced velocity-map ion imaging at various translational collision energies. Increase of vibrational energy from 16 194 to 18 922 cm(-1) does not make a sign...

Vibrational excitations of low frequency collective modes are essential for functionally important conformational transitions in proteins. Here we report the first direct measurement on the lifetime of vibrational excitations of the collective modes at 87 pm (115 cm(-1)) in bacteriorhodopsin, a transmembrane protein. The data show that these modes have extremely long lifetime of vibrational exc...