Surface Structure of Imidazolium-based Ionic Liquids: Quantitative Comparison between Simulations and High-resolution RBS Measurements.

0461334 - ÚCHP 2017 RIV US eng J - Journal Article
Nakajima, K. - Nakanishi, S. - Lísal, Martin - Kimura, K.
Surface Structure of Imidazolium-based Ionic Liquids: Quantitative Comparison between Simulations and High-resolution RBS Measurements.
Journal of Chemical Physics. Roč. 144, č. 11 (2016), s. 114702. ISSN 0021-9606. E-ISSN 1089-7690
R&D Projects: GA ČR GA16-12291S
Institutional support: RVO:67985858
Keywords : spectroscopy * rutherford backscattering spectroscopy * molten-salt
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 2.965, year: 2016

Elemental depth profiles of 1-alkyl-3-methylimidazolium bis(trifluoromethanesulfonyl) imide ([CnMIM][TFSI], n = 4, 6, 8) are measured using high-resolution Rutherford backscattering spectroscopy (HRBS). The profiles are compared with the results of molecular dynamics (MD) simulations. Both MD simulations and HRBS measurements show that the depth profiles deviate from the uniform stoichiometric composition in the surface region, showing preferential orientations of ions at the surface. The MD simulations qualitatively reproduce the observed HRBS profiles but the agreement is not satisfactory. The observed discrepancy is ascribed to the capillary waves. By taking account of the surface roughness induced by the capillary waves, the agreement becomes almost perfect.
Permanent Link: http://hdl.handle.net/11104/0260948