Laser excitation spectrum

In alkali atom experiments no explicit resonances have been observed in microwave ionization. However, there are indirect confirmations of the multiphoton resonance picture. First, according to the multiphoton picture the sidebands of the extreme n and n + 1 Stark levels should overlap if E = 1/3n5. In the laser excitation spectrum of Na Rydberg states from the 3p3/2 state in the presence of a 15 GHz microwave field van Linden van den Heuvell et al. observed sidebands spaced by 15.4 GHz, as shown in Fig. 10.15.18 The extent of the sidebands increases linearly with the microwave field, as shown in Fig. 10.15, and the n = 25 and n = 26 sidebands overlap at microwave fields of 150 V/cm or higher, matching the observation that the 25d state has an ionization threshold of 150 V/cm in a 15 GHz field. 

Figure 2. Laser-excitation spectrum for nitric oxide in N2 flowing from burner at atmospheric pressure (spectrometer set for 0,0 y-band at 2262.0 A)...

Fig. 5. High resolution laser excitation spectrum of the 0—0 band in the A2E—X n system of the OH radical. The widths of the peaks in the spectrum reflect the Doppler width of OH at room temperature, Ay 8 = 0.009 A. (After ref. 35.)...

Fluorescence lifetimes of the first excited singlet states of HSO and DSO. Analytical expression used to compute vibrational energy dependence of non-radiative rates Dye-laser excitation spectrum of A A (004) — X A (000) band of HSO... 

Simulation of the i.r. spectrum of ArHD from an accurate calculation of photodissociation cross-sections. Comparison with experiment Laser excitation spectrum of NaArjA H —... 

Figure 16. Laser excitation spectrum of the 000-000 band of the B22 + -X2S+ transition of SrOD. [Reprinted with permisssion from ref. 74. Copyright 1996 Academic Press.]...

Figure 18. Laser excitation spectrum of the C2A-X21.+ transition of CaOH. [Reprinted with permission from ref. 85. Copyright 1992 American Institute of...

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

Zare and co-workeis have demonstrated the high sensitivity of las -induced fluorescence in determination of internal state distributions of a wide range of reaction products formed under molecular beam conditions. As well as having made systematic lifetime determinations, Zare et al. could obtain a laser excitation spectrum by continuously scanning the wavelength of a tunable dye laser which excites a particular state of a reaction-product ground electronic state to a... 

Providing ancillary spectroscopic data is available, equation (17) permits extraction of relative ground-state vibrational populations from intensities of the laser excitation spectrum. Wavelength resolution of the fluorescence enables Franck-Condon factors to be calculated from relative intensities observed in emission from a single v level to a manifold of levels v" in the ground electronic state. 

The laser excitation spectrum of IF is simple, each band consisting of a / and R branch uncomplicated by isotopic splittings. Eight bands of the v = 0 progression (3 > v > 10) have been observed in laser excitation of the B—system. ... 

A predissociation was observed, as can clearly be seen in Figure 11, which shows the laser excitation spectrum recorded at both low resolution ( 0.01 nm) and high resolution ( 0.001 nm). Onset of breaking-off in fluorescence in the 10—0 band is observed at J 12, indicating that predissociation of the B state commences at an energy of (22 700 15) cm above " = 0 of the ground state. (Predissociation has been observed in laser excitation studies of the interhalogens IF, BrF, and ICl, and it will be discussed for each in turn.)... 

Taking the lower limit for Do(BrF) of 20 540 cm as suggested by Coxtm, corresponding to the thermochemical data used by the JANAF compilers, and adopting an upper limit of 20 880 cm derived from the laser excitation spectrum, we obtain 20 540 < >o (BrF) < 20 880cm, which differs significantly from the estimate of Brodersen and Sicre (19 263 30 cm ) obtained from the absorption spectrum. ... 

Figure 12 Laser excitation spectrum of the (6,0) band ofBrF,, at 0.01 nm laser bandwidth...

Fig. 9 Laser excitation spectrum arising from X 2/2 3 showing...

Fig. 10 Laser excitation spectrum of the vinoxy radical showing resolved rotational structure, with the assignments as indicated.

Fig. 11 Laser excitation spectrum of the ethoxy radical showing rotational structure with the indicated assignments.

Fig. 12. The laser excitation spectrum of CH Se. The inset is a higher sensitivity scan of the...

Fig. 15. The laser excitation spectrum of jet-cooled CBr S. The asterisks denote impurity bands...

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