Relaxation processes in room temperature ionic liquids: The case of 1-butyl-3-methyl imidazolium hexafluorophosphate


Autoria(s): Triolo, A.; Russina, O.; Hardacre, Christopher; Nieuwenhuyzen, Mark; Gonzalez, M.A.; Grimm, H.
Data(s)

24/11/2005

Resumo

A detailed investigation on the nature of the relaxation processes occurring in a typical room temperature ionic liquid (RTIL), namely, 1-butyl-3-methyl imidazolium hexafluorophosphate ([bmim][PF6]), is reported. The study was conducted using both elastic and inelastic neutron scattering over a wide temperature range from 10 to 400 K, accessing the dynamic features of both the liquid and glassy amorphous states. In this study, the inelastic fixed energy scan technique has been applied for the first time to this class of materials. Using this technique, the existence of two relaxation processes below the glass transition and a further diffusive process occurring above the glass-liquid transition are observed. The low temperature processes are associated with methyl group rotation and butyl chain relaxation in the glassy state and have been modeled in terms of two Debye-like, Arrhenius activated processes. The high temperature process has been modeled in terms of a Kohlraush-Williams-Watts relaxation, with a distinct Vogel-Fulcher-Tamman temperature dependence. These results provide novel information that will be useful in rationalizing the observed structural and dynamical behavior of RTILs in the amorphous state.

Identificador

http://pure.qub.ac.uk/portal/en/publications/relaxation-processes-in-room-temperature-ionic-liquids-the-case-of-1butyl3methyl-imidazolium-hexafluorophosphate(0787ce8a-807c-4173-967f-7298b8d6c12f).html

http://dx.doi.org/10.1021/jp053355j

http://www.scopus.com/inward/record.url?scp=28944450416&partnerID=8YFLogxK

Idioma(s)

eng

Direitos

info:eu-repo/semantics/restrictedAccess

Fonte

Triolo , A , Russina , O , Hardacre , C , Nieuwenhuyzen , M , Gonzalez , M A & Grimm , H 2005 , ' Relaxation processes in room temperature ionic liquids: The case of 1-butyl-3-methyl imidazolium hexafluorophosphate ' Journal of Physical Chemistry B , vol 109 (46) , no. 46 , pp. 22061-22066 . DOI: 10.1021/jp053355j

Palavras-Chave #/dk/atira/pure/subjectarea/asjc/1600/1606 #Physical and Theoretical Chemistry
Tipo

article