Boltzmann temperature

The first-order non-isothermal (FONI) reactor. A continuous, well-stirred magmatic reservoir similar to those discussed above is supposed to be thermally insulated. A dissolved element i precipitates with a temperature-dependent rate of crystallization. Crystallization rate is assumed to obey first-order kinetics with Boltzmann temperature dependence such as... 

The plasmas are in a nonequilibrium state in which the Boltzmann temperature of the electrons is roughly two orders of magnitude higher than that of the gas ions and molecnles. This lack of thermal equilibrinm makes it possible to obtain a plasma in which the gas temperature is near ambient conditions, while the electrons... 

This allows us to solve for the Boltzmann temperature TBoitz ... 

By examining the excitation spectrum of a molecular species one can deduce a ground state Boltzmann temperature. Also, as will be discussed below, if one can predict the population distribution in the atom or molecule under excitation conditions, then one can use the observed fluorescence spectrum to recover the gas temperature. 

The X — B emission spectrum of CN measured at 0.25 cm-1 resolution is shown in Figure 19. The CN radical in its B state was produced by coexpanding 100 torr of acetonitrile (CH3CN) with 1 atm of helium in the corona discharge source. The spectrum includes both the 0-0 and 1-1 transitions. An analysis of the rotational distributions in both the v = 0 and 1 levels revealed a Boltzmann temperature of... 

The rotational and vibrational distributions of the CN(X X ) fragment resulting from the collisionless IRMPD of CF CN have been measured using LIF and compared with the predictions of statistical theories. The distributions could be characterized in terms of Boltzmann temperatures, with Tv = 2400 200K and T,= 1200 100 K. Such Boltzmann behaviour could be... 

The 0 term is a Boltzmann temperature, T, factor the <1) term is a Debye-Waller (DW) factor, well known from diffraction work and finally, the I are Bessel functions of the first kind. This single, simple, harmonic system is quite unrepresentative of any realistic molecular solid, however, it is instructive to express the equation with appropriate experimental parameters. The translational optic modes of water (see below) appear at about 35 meV (260 cm ) and typical experimental temperatures are about 20 K (= 2 meV). 

They found that the rotational populations of high and low rotational levels of the e n state were expressed by double Boltzmann temperatures of 903 and 492 K at 1.4 Torr and 878 and 278 K at 250 Torr, respectively. Collins and Robertson examined the axial variation and pressure dependence of the intensity of the He2 emission and HeJ concentration, and identified the dominant populating meehanism of He2 to be recombination process 27. 

Maxwell-Boltzmann temperature distribution - based on classical statistics, gives the number of molecules in a gas whose total velocity lies within a given range. 

The influence of the magnetic field on the energy of the ground level results in a Boltzmann temperature-dependent redistribution of the population between the sublevels of A. The population of the sublevel a will now be given by... 

In this case the bandwidth of the probe laser is sufficiently broad to overlap several rotational lines. Still, we can estimate that K, 23—27 corresponding to a Boltzmann temperature of >3000 K. In more recent experiments, using a narrower bandwidth laser, we have been able to resolve individual rotational lines as shown in Eig. 4. By plotting against K, a bimodal distribution is found, which can adequately be fitted to two Boltzmann temperatures, 105 K and 3520 K, as shown in Eig. 5. 

This population of electronically excited states decreases exponentially with effective Boltzmann temperature 7 and has an absolute value corresponding to equilibrium with continuumy(ii) y y. In the opposite case, the population of electronically excited states far from continuum (E > Te) can be found as... 

Basic Theory. We consider first an ideal resonance lamp, emitting a non-reversed Doppler-shaped line at a Boltzmann temperature T,. Since most actual lamps operate at low pressures, pressure-broadening is small, as is natural broadening. 

Boltzmann temperature dependence. What the data do resemble is the temperature dependence typical of strongly spin-orbit-split states [15], where second-order Zeeman terms yield [5,22,23] unusual temperature dependences, and, in particular, large TIP terms because of mixing of the spin-orbit states by the magnetic field. 

The rotational distribution was fitted to a Boltzmann temperature of 650 50 K and was independent of scattering angle. 

Except for unsaturated molecules (see Section 2.4.6), most reactions of O atoms with stable molecules do not yield CO as a product. However, reac-tion of O atoms with organic radicals, especially carbenes, do yield CO. The reactions of CH2 with O2 and CO2 also yield CO. " All of these reactions appear to give CO vibrational distributions characteristic of long-lived complexes, i.e., they can be described by a high Boltzmann temperature. 

V levels. The BaCl rotational distributions were fitted to Boltzmann temperatures and Tr declined from 5200 to 2500 K as t increased from 0 to 15. The (-Ft) showed an even stronger inverse correlation and changed from 3.4 to 0 kcal mole" as v increased from 0 to 15. Based upon phase space calculations for the shapes of the distributions, the energy was not equilibrated within the mean lifetime (1.5 x 10" s) however, the fractions given in Table 2.19 do resemble the cases where statistical partitioning was found (for Et). 

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