The B2Σ+ ← X2Σ+ Transition of HgI

A Theoretical Study of the Oxidation of Hg0to HgBr2in the Troposphere

“…Interestingly, for HgBr the theoretical estimate of k 4 is about a factor of 3 lower than the recent experimental measurement (). In fact, we can only match the experimental value if the bond energy of HgBr is increased to over 100 kJ mol -1 , about 30 kJ mol -1 higher than the current experimental measurement of 74.9 ± 4 kJ mol -1 ( , ). However, the recent experimental estimate of k 4 was a relative rate measurement that required several significant correction factors ().…”

“…However, the recent experimental estimate of k4 was a relative rate measurement that required several significant correction factors (11). Therefore, for the present calculations, we prefer the theoretical estimate of k4 since the vibrational frequency and rotational constant of HgBr used in the present application of RRKM theory are known precisely from laser-induced fluorescence spectroscopy in a supersonic jet (22). In any case, we will show below that the crucial factor that determines the lifetime to convert Hg 0 to Hg II is the rate at which HgBr decomposes (reaction -4).…”

Ion-pair state spectroscopy of HgCl

“…The presence of the atomic lines (Table 1) in the HgCl spectrum was expected, given a similar observation in our previous studies (10,11). In this work the frequency measurements for the He lines are, for the most part, in better agreement with the literature values (12) than those for Hg, in the same frequency region.…”

Anisotropy Measurements of Solvated HgI2Dissociation: Transition State and Fragment Rotational Dynamics

“…If indeed both states are pumped, the observed initial anisotropy of HgI is expected to be the combination of the respective canonical anisotropies listed in Table . In the following, it will be assumed that a 2 Σ → 2 Σ transition of HgI is probed, as is the case in the gas phase. − Furthermore, according to Table , if the probed transition of HgI were a Σ → Π transition, the anisotropy should never exceed 0.1, regardless of which HgI 2 transition were to be pumped, whereas an anisotropy of 0.16 was observed after excitation at 270 nm. From the initial anisotropy of 0.05 after excitation at 320 nm (determined by interpolation of the anisotropy data for HgI back to time zero assuming inertial dynamics, as described above), it can be concluded that the absorption of HgI 2 in ethanol at this wavelength must be composed of both 1 Π (58%) and 1 Σ - (42%) contributions.…”