Transient phase grating spectroscopy

Miller and coworkers studied the energy flow between the protein and solvent using transient phase grating spectroscopy, which can monitor the temperature of the solvent matrix [39]. They demonstrated that energy transfer to the surrounding solvent occurred within 20 ps mediated by the protein backbone. A nanosecond time-scale was also observed, which was attributed to the slow conformational relaxation of the protein globin [40]. 

Walther, M., Raicu, V., Ogilvie, J. R, Phillips, R., Kluger, R., and MiUer, R. J. D. 2005. Determination of the Pe-CO bond energy in myoglobin using heterodyne-detected transient thermal phase grating spectroscopy. J. Phys. Chem. B 109 20605-11. 

Genberg, L., Bao, Q., Bracewski, S., Miller, R.J.D. Picosecond transient thermal phase grating spectroscopy a new approach to the study of vibrational-energy relaxation processes in proteins. Chem. Phys. 131, 81-97 (1989)... 

Figure 3 Folded BOXCARS geometry applied in several transient nonlinear optical spectroscopies. In pump-probe spectroscopy, one of the three beams is blocked and the intensity of one of the incoming beams is monitored as a function of the time delay between the remaining two beams (e.g., beam 3 is blocked and beam 2 is monitored as a function of its delay with respect to beam 1, phase-matching condition would be k2 = ki — ki -I- k2>. Beams 4 and 5 are photon echo signals generated from beams 1 and 2. Beams 6 and 7 can be stimulated photon echo or transient grating signals generated from beams 1,2, and 3. In transient grating two of the beams are time coincident. In coherent anti-Stokes Raman spectroscopy, beams 1 and 3 are time coincident and carry the same frequency the difference between this frequency and that of beam 2 (so-called Stokes beam) matches a vibrational frequency of the system and beam 6 will correspond to the anti-Stokes emission.

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