Collisional quenching of excited iodine atoms I(5p52P1/2) BY I2

Electronic-to-Vibrational Energy Transfer from I(52P1/2)to I2(25<v<43)

“…The result is not Gaussian, but, since the laser line width is almost 20 times greater than the absorption line widths, the use of the average measured widths and Gaussian profiles is adequate. Thus, for the ith rotational line considered, we compute the contribution to the absorption at wavenumber p as k¡(p) = k0i exp 2(In 2)VHp ~voi) Ap (17) The total absorption coefficient at p, k" is the sum of contributions from all nearby lines: K = ) (18) The fraction of light absorbed at wavenumber p in 1 cm of optical path in the region viewed by the detector (32 cm inside the cell) is absorbed fraction/cm = e"*»'32(l -e~*'-1) (19) For a laser beam with a Gaussian frequency distribution, I(p), the total density of excited states in front of the detector is NuB) = fjl(p) e~kr'32(le-*d dp (20) where I(p) is expressed in photons/(cm2 pulse cm"1), and the total fluence I0, in photons/(cm2 pulse), is given by /"= Cl(p) dp (21)…”

Energy Relaxation Dynamics of Photofragments Measured by Probe Beam Deflection Technique: Photodissociation of CF3I at 266 nm

“…In the present study, concentrations of photofragment radicals, CF 3 and I, were kept low (≤4 × 10 -3 Torr) in order to suppress the radical combination reactions. With the given radical concentrations, it is estimated that the recombination reactions among them take place on the millisecond time scale, , which is too slow to be detected in the present experimental setup. For gas-phase species (at atmospheric pressure and at room temperature), T−T and R−T energy transfers as well as V−V and R−R energy transfers are known to occur on a time scale of molecular collisions, , ca.…”

Spin‐orbit excitation in the system I + I2: Relativistically parameterized extended‐Hückel calculations

“…For the all-iodine reactions of Table 11, detailed experimental investigation would require difficult isotope labeling studies. However, the sum of the rate constants for the nonconservation reactions (4c) and (4d) has been determined as (3.6k0.3) X lo-" cm3/s by Burde et al, who also cite results from other workers ranging from 4.1 X to 8.2 X lo-" cm3/s [20]. These values are sufficiently large to be interesting in the context of a hard sphere collision rate constant of about 3 x lo-'' cm3/s (at 300 K), which provides an upper limit for the conservation reactions (4a) and (4b).…”