eprintid: 1474806 rev_number: 24 eprint_status: archive userid: 608 dir: disk0/01/47/48/06 datestamp: 2016-02-17 16:13:02 lastmod: 2021-09-19 23:46:55 status_changed: 2016-02-17 16:13:02 type: article metadata_visibility: show creators_name: Mercy, M creators_name: Taylor, SF creators_name: Jacquemin, J creators_name: Hardacre, C creators_name: Bell, RG creators_name: De Leeuw, NH title: The addition of CO₂ to four superbase ionic liquids: a DFT study ispublished: pub divisions: UCL divisions: B04 divisions: C06 divisions: F56 note: This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. abstract: The addition of carbon dioxide to four superbase ionic liquids, [P3333][Benzim], [P3333][124Triz], [P3333][123Triz] and [P3333][Bentriz] was studied using a molecular DFT approach involving anions alone and individual ion pairs. Intermolecular bonding within the individual ion pairs is characterised by a number of weak hydrogen bonds, with the superbase anion geometrically arranged so as to maximize interactions between the heterocyclic N atoms and the cation. The pairing energies show no correlation to the observed CO2 adsorption capacity. Addition of CO2 to the anion alone clearly resulted in the formation of a covalently-bound carbamate function with the strength of binding correlated to experimental capacity. In the ion pair however the cation significantly alters the nature of the bonding such that the overall cohesive energy is reduced. Formation of a strong carbamate function occurs at the expense of weakening the interaction between anion and cation. In the more weakly absorbing ion pairs which contain [123Triz](-) and [Bentriz](-), the carbamate-functionalised systems are very close in energy to adducts in which CO2 is more weakly bound, suggesting an equilibrium between the chemi- and physisorbed CO2. date: 2015-11-21 date_type: published official_url: http://dx.doi.org/10.1039/c5cp05153c oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green article_type_text: Journal Article verified: verified_manual elements_id: 1086604 doi: 10.1039/c5cp05153c language_elements: eng lyricists_name: Bell, Robert lyricists_name: De Leeuw, Nora lyricists_id: RGBEL28 lyricists_id: NHDEL32 actors_name: Gibson, Alice actors_id: AGIBS47 actors_role: owner full_text_status: public publication: Physical Chemistry Chemical Physics volume: 17 number: 43 pagerange: 28674-28682 event_location: England issn: 1463-9084 citation: Mercy, M; Taylor, SF; Jacquemin, J; Hardacre, C; Bell, RG; De Leeuw, NH; (2015) The addition of CO₂ to four superbase ionic liquids: a DFT study. Physical Chemistry Chemical Physics , 17 (43) pp. 28674-28682. 10.1039/c5cp05153c <https://doi.org/10.1039/c5cp05153c>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/1474806/1/c5cp05153c%281%29.pdf