Jump to main content
Jump to site search
PLANNED MAINTENANCE Close the message box

Scheduled maintenance work on Wednesday 22nd May 2019 from 11:00 AM to 1:00 PM (GMT).

During this time our website performance may be temporarily affected. We apologise for any inconvenience this might cause and thank you for your patience.


Issue 31, 2017, Issue in Progress
Previous Article Next Article

Preferential stabilization of HeI2 van der Waals isomers: the effect of energetics and temperature

Author affiliations

Abstract

The populations of the two different HeI2 conformers (linear and T-shaped) were calculated as a function of temperature using a simple thermodynamic model and the quantum mechanical partition functions for each conformer. Variational quantum calculations were performed for angular momentum values J up to 15, and by analyzing the rovibrational energies and functions, all states up to dissociation were assigned. On the basis of the vibrational and rotational partition functions calculations, it was found that the relative populations of the isomers have a strong dependence on the temperature. The population of the linear isomer (the most stable one according to the ab initio CCSD(T)/CBS potential used) decreases relative to that of the T-shaped, as the temperature increases, and at temperatures around 1 K the two populations are equal, with the T-shaped isomer being more abundant for higher temperatures. The temperature effect on the relative population was also investigated as a function of the difference in the binding energy values of the two isomers, including those determined from the experimental observations with the T-shaped being energetically most stable. In this case, even though the ratio of the T-shaped/linear populations decreases rapidly for temperatures below 1 K, the T-shaped isomer was the most abundant at all temperatures. The system evolves between both T-shaped and linear arrangements, with no significant changes at temperatures 1.5 K. The disagreement at low temperatures between theoretical predictions and experimental data available indicates that further refinement is still needed for controlling the isomers' formation, and various possible sources of errors are extensively discussed.

Graphical abstract: Preferential stabilization of HeI2 van der Waals isomers: the effect of energetics and temperature

Back to tab navigation

Publication details

The article was received on 02 Feb 2017, accepted on 17 Mar 2017 and first published on 31 Mar 2017


Article type: Paper
DOI: 10.1039/C7RA01378G
RSC Adv., 2017,7, 19273-19279
  • Open access: Creative Commons BY license
  •   Request permissions

    Preferential stabilization of HeI2 van der Waals isomers: the effect of energetics and temperature

    Á. Valdés and R. Prosmiti, RSC Adv., 2017, 7, 19273
    DOI: 10.1039/C7RA01378G

    This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Material from this article can be used in other publications provided that the correct acknowledgement is given with the reproduced material.

    Reproduced material should be attributed as follows:

    • For reproduction of material from NJC:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the Centre National de la Recherche Scientifique (CNRS) and the RSC.
    • For reproduction of material from PCCP:
      [Original citation] - Published by the PCCP Owner Societies.
    • For reproduction of material from PPS:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the European Society for Photobiology, the European Photochemistry Association, and RSC.
    • For reproduction of material from all other RSC journals:
      [Original citation] - Published by The Royal Society of Chemistry.

    Information about reproducing material from RSC articles with different licences is available on our Permission Requests page.

Search articles by author

Spotlight

Advertisements