title: Temperature effects on the viscosity and the wavelength-dependent refractive index of imidazolium-based ionic liquids with a phosphorus-containing anion.
abstract: A systematic study on the viscosity and refractive index of 1-alkyl-3-methylimidazolium based ionic liquids (alkyl = methyl, butyl and hexyl) combined with three phosphorus containing anions, i.e. dimethylphosphate, methyl methylphosphonate and methylphosphonate, is reported. Experimental measurements account for temperature effects, while the refractive index is determined at multiple wavelengths in the visible and near infrared region. Despite the structural similarity of these anions, significant differences in the physical properties of the resulting ILs are identified, along with the clear trend of viscosity increase - and refractive index decrease - with increasing alkyl chain length on the cation. Ab initio theoretical calculations are carried out to support and rationalise the observed behaviour.
authors.affiliation: Dipartimento di Farmacia, Università di Pisa, via Bonanno 33, 56126 Pisa, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Chiappe
authors.affiliation: Dipartimento di Farmacia, Università di Pisa, via Bonanno 33, 56126 Pisa, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Margari
authors.affiliation: Dipartimento di Farmacia, Università di Pisa, via Bonanno 33, 56126 Pisa, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Mezzetta
authors.affiliation: Dipartimento di Farmacia, Università di Pisa, via Bonanno 33, 56126 Pisa, Italy.
authors.forename: C S
authors.initials: CS
authors.lastname: Pomelli
authors.affiliation: Laboratory of Electronic Devices and Materials, Department of Electronic Engineering, Technological Educational Institute of Athens, Athens, Greece. moutzouris@teiath.gr.
authors.forename: S
authors.initials: S
authors.lastname: Koutsoumpos
authors.affiliation: Laboratory of Electronic Devices and Materials, Department of Electronic Engineering, Technological Educational Institute of Athens, Athens, Greece. moutzouris@teiath.gr.
authors.forename: M
authors.initials: M
authors.lastname: Papamichael
authors.affiliation: Laboratory of Electronic Devices and Materials, Department of Electronic Engineering, Technological Educational Institute of Athens, Athens, Greece. moutzouris@teiath.gr.
authors.forename: P
authors.initials: P
authors.lastname: Giannios
authors.affiliation: Laboratory of Electronic Devices and Materials, Department of Electronic Engineering, Technological Educational Institute of Athens, Athens, Greece. moutzouris@teiath.gr.
authors.forename: K
authors.identifier: http://orcid.org/0000-0003-3486-5865
authors.initials: K
authors.lastname: Moutzouris