Dispersed fluorescence spectrum

The vibrogram analysis [108] based on the dispersion fluorescence spectrum of acetylene by Solina et al. [125] reveals a recurrence around 50 fs from 0 to 12,000 cm"1, which is similar to the one in the previous analysis. However, an important recurrence appears at 70 fs at higher energies from 4000 to 16,000 cm 1, which is caused either by anharmonic period lengthening or by a transition to a slower regime at higher energies. 

Figure 5. Dispersed fluorescence spectrum and fluorescence decay resulting from excitation of jet-cooled anthracene to S, + 766 cm 1 (122). The fluorescence spectrum was obtained with 1.6 A monochromator resolution (sR). An arrow marks the excitation wavelength. The decay corresponds to detection of the vj = 390 cm 1 band in the spectrum with R — 3.2 A.

It is possible to record a dispersed fluorescence spectrum where the only lines present are a vibrational progression of R, P doublets that correspond to a single set of lower electronic state rotational combination differences,... 

Figure 1.15 Dispersed Fluorescence Spectrum of AgAu. The AgAu A — X1 E+ DF spectrum contains long v —> v" vibrational progressions because the bond length in the A-state is much longer than in the X-state. The nodal structures of the v = 0, 2, and 3 vibrational states are displayed as intensity minima in the DF spectra. Since the vibrational quantum number is equal to the number of internal nodes in the wavefunction, a vibrational progression in an absorption or DF spectrum often reveals the absolute assignment of the initial vibrational state (from Fabbi, el al., 2001).

Figure 20. The dispersed fluorescence spectrum of the A X and B-X transitions of SrOC(NH)H. The laser is exciting the 0-0 band of the B-X transition. [Reprinted with permission from ref. 93. Copyright 1990 American Chemical Society.]...

Figure 13. Laser-induced fluorescence spectra of the CF3O radical (a) laser excitation spectrum b) dispersed fluorescence spectrum.

The possibilities of molecular beam spectroscopy can be enhanced by allowing for spectrally resolved fluorescence detection or for resonant two-photon ionization in combination with a mass spectrometer. Such a molecular beam apparatus is shown in Fig. 4.5. The photomultiplier PMl monitors the total fluorescence /r(A.l) as a function of the laser wavelength Xl (excitation spectrum. Sect. 1.3). Photomultiplier PM2 records the dispersed fluorescence spectrum excited at a fixed laser... 

Fig. 4.5 Experimental setup for sub-Doppler spectroscopy in a collimated molecular beam. Photomultiplier PMl monitors the total undispersed fluorescence, while PM2 behind a monochromator measures the dispersed fluorescence spectrum. The mass-specific absorption can be monitored by resonant two-color two-photon ionization in the ion source of a mass spectrometer...

Figure 7.5 Dispersed fluorescence spectrum of formaldehyde CH2O) following laser excitation of its X —A 4-5K(2) R(6) transition. Information on the energy-level structure and transition probabilities can be extracted from the line positions and the line intensities. Experimental data adapted from Klein-Duwel et al Appl. Opt., 2000, 39 3712, with permission of the Optical Society of America...

Fig. 5. Dispersed fluorescence spectrum from OH A(v =0) products following vibrational predissociation of OH-Ar complexes with one quantum of OH vibrational excitation.

Fig. 3. Dispersed fluorescence spectrum of the fragment emission of tetrazine after excitation of the 6a level of the cluster.

J. Tellinghuiser, A. Ragone, M. S. Kim, D. J. Auerbach, R. E. Smalley, L. Wharton, and D. H. Levy, The dispersed fluorescence spectrum of NaAr Ground and excited state potential curves,... 

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