English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The temperature dependence of the gas-phase collisional relaxation of highly vibrationally excited aromatic molecules has been studied using large scale classical trajectory calculations. The investigations have focused on azulene collisions with different colliders (He, Ar and N 2 ) as well as pyrazine self-collisions providing the moments of energy transfer &lt;Δ E &gt; and &lt;Δ E  2 &gt;in the temperature range 50-1500 K. The interaction well depth ε eff / k  B  is found to be the key factor controlling the observed  T  dependence of collisional energy transfer. Systems with a relatively deep interaction well (pyrazine + pyrazine, azulene + Ar, azulene + N 2 ) show a pronounced negative dependence of -&lt;Δ E &gt; when  T  &lt; ε eff / k  B  (in the systems studied here roughly at   T  &lt; 300-400 K). The increased efficiency of collisional energy transfer at low T is due to additional contributions from collisions at large impact parameters. In systems with a very shallow well (azulene + He), however, a positive  T  dependence is found in the low temperature regime (&lt; 300 K) due to the dominant contributions from impulsive, adiabatic collisions at  short  impact parameters. At higher temperatures ( T  &gt; 300-400 K) - when the temperature is well above ε eff / k  B  - all systems behave qualitatively similar, showing only a very weak, slightly negative  T  dependence, as long as one is still far away from thermal equilibrium.

Temperature Dependence of Collisional Energy Transfer in Highly Excited Aromatics Studied by Classical Trajectory Calculations