Rydberg atoms constant

The physical significance of this expression is that the rate constant for elastic perturber-Rydberg atom collisions is the same as the rate constant for elastic perturber-electron collisions averaged over the Rydberg electron s velocity distribution, in spite of the fact that V v. 

As is the case for Eq. (11.31), Eq. (11.32) states explicitly that the rate constant for Rydberg atom scattering is the same as the rate constant for free electron scattering averaged over the Rydberg electron velocity distribution. 

Fig. 11.22 Rate constants k and cross sections o for CS2- formation in collisions of Ne ns (O) and nd ( ) Rydberg atoms with CS2 molecules vs n. The decrease of the rate constant and cross section for n > 20 is due to the reduced probability of stabilizing Ne+—CSj ...

The use of the weakly bound electron in a Rydberg atom to measure low energy electron attachment rate constants has proven to be one of the more useful applications of Rydberg atoms. Measurements have been refined to the point of measuring the lifetimes of negative ions formed by attachment,96 and it is likely that further developments will follow. 

Table 11.2. Experimental and calculated rate constants for deflection of Li Rydberg atoms by five target gases.a...

The Rydberg constant is one of the most important constants of atomic physics because of its connection with the fundamental atomic constants (e, h, m c) and because of the high accuracy with which it can be determined. 

Interpretation of the most precise measurements in atomic physics with the best ah initio theories leads to values of the fundamental constants, which reflect relations between phenomena in the different realms of physics, and which can be regarded as the ultimate base units of physical measurement. In the past decades, a revolution has occurred in our system of measurements, whereby the accuracy of many of the fundamental physical constants, especially of the atomic constants (such as the Rydberg constant), has caught up with our ability to realise the definitions of many of the SI units [2, 3]. 

Figure 18. Relative rate constants for the production of (CH3N02) anions in electron transfer reactions between laser excited Cs(ns), Cs nd, Xe nf), Rb(nc(), and Rb(ns) Rydberg atoms and nitromethane molecules.

Rydberg constant so deduced for hydrogen was then compared with that for deuterium or ionized helium in order to obtain a value for the atomic mass of the electron (section 3.4). This result, divided into the Faraday, gave a spectroscopic5 value of ejm for comparison with the deflection5 value, which at one time appeared to differ significantly [10]. Recent assessments of the best values of the. atomic constants [39] do not maintain this distinction, which has mainly been resolved by the use of more reliable observational material. The agreement of spectroscopic and deflection values of ejm therefore supports the... 

Alilfikan s oil-drop experiment settled the argument and determined accurately (within one part in a thousand) both the charge and, by virtue of the charge-to-mass ratio, the mass of the electron. Both numbers allowed the Danish physicist Niels Bohr to finally calculate Rydberg s constant and provided the first and most important proof of the new atomic theory. 

Figure 5 Left panel Rate constants k for electron attachment to as a function of the mean collisional energy. (From Ref. 118.) (O) The results obtained using the pulse radiolysis microwave cavity technique combined with microwave electron heating ( ) previous results by Shimamori et al. [J. Chem. Phys. 1993, 99, 7789] ( ) electron swarm [Spyrous and Christophorou, J. Chem. Phys. 1985, 82, 1048] and (O) high-Rydberg atom beams [Marawar et al., J. Chem. Phys. 1988, 88, 2853]. Right panel Comparison of the cross section cr(s) for attachment to C5F5 as a function of the electron energy, (—) derived by unfolding the rate constants (From Ref. 118.) with the previous cross...

For p(Ar) >0.7 mbar (0.5 torr) the argon begins to diffuse into the central part, if the temperature and thus the lithium vapor pressure remains constant while / (Ar) increases. The slope of the curve Aco(p) yields for p > 0.7 mbar the cross section for LiJ + Ar collisions. For the example depicted in Fig. 8.5 the cross sections for line broadening are (LiJ + Li) = 60 nm and (Li + Ar) =41 nm, whereas the line shifts are dvjdp — —26 MHz/mbar for Li + Ar collisions [981]. Similar measurements have been performed on Sr Rydberg atoms [982], where the pressure shift and broadenings of Rydberg levels R n) for the principle quantum numbers n in the range S [Pg.435]

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