The reactions of ground and excited state sodium atoms with hydrogen halide molecules

Weiss, Paul S.; Mestdagh, J. M.; Covinsky, Michael; Balko, Barbara A.; Lee, Y.T.

doi:10.1016/0301-0104(88)85023-7

Cited by 49 publications

(22 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…We have also considered the reactivity of the excited alkali atom states with HCl. Weiss et al (1988) have shown that the reactivity to form NaCl, increases with increasing state energy for the states 3S, 3P, 5S and 4D. They measured an average cross section of ∼4Å 2 for the Na[3P] state, while for the other states we consider here we estimated a cross section of 10Å 2 for reaction based on their results.…”

Section: Excited State Chemistrymentioning

confidence: 95%

Electron Densities and Alkali Atoms in Exoplanet Atmospheres

Lavvas

Koskinen

Yelle

2014

ApJ

View full text Add to dashboard Cite

We describe a detailed study on the properties of alkali atoms in extrasolar giant planets, and specifically focus on their role in generating the atmospheric free electron densities, as well as their impact on the transit depth observations. We focus our study on the case of HD 209458 b, and we show that photoionization produces a large electron density in the middle atmosphere that is about two orders of magnitude larger than the density anticipated from thermal ionization. Our purely photochemical calculations though result in a much larger transit depth for K than observed for this planet. This result does not change even if the roles of molecular chemistry and excited state chemistry are considered for the alkali atoms. In contrast, the model results for the case of exoplanet XO-2 b are in good agreement with the available observations. Given these results we discuss other possible scenarios, such as changes in the elemental abundances, changes in the temperature profiles, and the possible presence of clouds, which could potentially explain the observed HD 209458 b alkali properties. We find that most of these scenarios can not explain the observations, with the exception of a heterogeneous source (i.e. clouds or aerosols) under specific conditions, but we also note the discrepancies among the available observations. Subject headings: planetary systems planets and satellites: atmospheres, composition, individual (HD 209458 b, XO-2 b)

show abstract

Section: Excited State Chemistrymentioning

confidence: 95%

Electron Densities and Alkali Atoms in Exoplanet Atmospheres

Lavvas

Koskinen

Yelle

2014

ApJ

View full text Add to dashboard Cite

show abstract

“…There has been a growing interest in the spectroscopy of the Na ··· HF van der Walls interactions, in which the rovibrational spectrum of these molecules is important to understand the nature of such intermolecular interactions 1–8. Furthermore, the Na + HF reaction is of great interest for both experimentalist and theorists because of its role in several important chemical process 9–13.…”

Section: Introductionmentioning

confidence: 99%

Evidence to support that adventitial cysts, analogous to intraneural ganglion cysts, are also joint‐connected

et al. 2012

View full text Add to dashboard Cite

Cystic adventitial disease (CAD) is a rare condition in which cyst is found within a vessel, typically producing symptoms of vascular compromise. Most commonly located in the popliteal artery near the knee, it has been reported in arteries and veins throughout the body. Its pathogenesis has been poorly understood and various surgical approaches have been recommended. We extrapolated some recent information about a similar condition, intraneural ganglion cyst affecting the deep fibular (peroneal) nerve, to the prototype, CAD of the popliteal artery. In intraneural ganglion cysts affecting the deep fibular nerve we have shown that an articular (neural) branch is the conduit between the superior tibiofibular joint and the main parent nerve for which epineurial dissection of joint fluid can occur. We hypothesized that the same principles would apply to CAD and that an articular (vascular) branch would be the conduit from the knee joint leading to dissection to the main parent vessel. We reviewed five patients with CAD of the popliteal artery in whom MRIs were available: two treated by the primary author well familiar with the proposed articular theory, and three treated by others at our institution, less familiar with it. We then reviewed the literature critically to assess for additional evidence to support our articular (synovial) theory and an anatomic explanation. In the two cases treated by the primary author a joint connection was identified on high resolution MRI prospectively and intraoperatively through the middle genicular artery (MGA); postoperatively in these cases there was no recurrence. In the other three cases, a joint connection was not identified on imaging or at operation. Reinterpretation of these cases revealed a joint connection through the MGA in the one patient who had preoperative imaging and subclinical persistence/recurrence in the two patients who underwent postoperative MRIs done for other reasons. Our review of the literature and imaging studies revealed unrecognized joint connections in CAD to the knee and other joints as well as evidence that the MGA is the conduit in cases of CAD of the popliteal artery. We believe that adventitial cysts originate in neighboring joints and dissect within articular (vascular) branches. In our opinion, the unifying articular theory and the principles introduced for intraneural ganglion cysts apply equally to common and rare sites of adventitial cysts.

show abstract

“…Alkali or alkaliearth atoms ͑M͒ with hydrogen halide molecules ͑HX͒ are good examples for which there are many experimental studies determining the effects of reagent excitation vibrational, 1-5 rotational 6-10 and electronic [11][12][13][14] excitation. It is particularly interesting the determination of the role of the transition state on the reaction dynamics, mainly for energies close to the threshold, and the M ϩHX systems present a wide variety of situations, the reactions being endothermic, exothermic or thermoneutral depending on the nature of the metal atom ͑M͒ and of the hydrogen halide molecule ͑HX͒, and on the initial excitation of the reactants.…”

Section: Introductionmentioning

confidence: 99%

Quantum stereodynamics of the Li+HF(v,j) reactive collision for different initial states of the reagent

Lara

Aguado

Roncero

et al. 1998

The Journal of Chemical Physics

View full text Add to dashboard Cite

The effect of the reagent initial state excitation on the reactive cross section in the LiϩHF(v, j) collision is analyzed for vϭ0, 1 and jϭ0, 1, 2 and 3. A wave packet treatment is used within the centrifugal sudden approximation on a global potential energy surface recently proposed ͓Aguado et al., J. Chem. Phys. 107, 10085 ͑1997͔͒. The reaction cross-section for vϭ0 is in good agreement with the available experimental data, and for low j shows oscillations as a function of the translational energy which are due to the structure of the transition state. For vϭ1 the reaction cross-section increases by a factor of 10-50 with respect to that of vϭ0. The influence of the alignment of the initial angular momentum on the reaction cross section is studied.

show abstract

The reactions of ground and excited state sodium atoms with hydrogen halide molecules

Cited by 49 publications

References 37 publications

Electron Densities and Alkali Atoms in Exoplanet Atmospheres

Electron Densities and Alkali Atoms in Exoplanet Atmospheres

Evidence to support that adventitial cysts, analogous to intraneural ganglion cysts, are also joint‐connected

Quantum stereodynamics of the Li+HF(v,j) reactive collision for different initial states of the reagent

Contact Info

Product

Resources

About