File(s) under permanent embargo
Rotational and translational mobility of a highly plastic salt : Dimethylpyrrolidinium thiocyanate
journal contributionposted on 15.02.2008, 00:00 authored by J Adebahr, M Grimsley, N Rocher, D MacFarlane, Maria ForsythMaria Forsyth
Thermal analysis, impedance spectroscopy, NMR and Raman spectroscopy have been used to investigate the plastic crystal dimethylpyrrolidinium thiocyanate in order to gain further insight into the properties of organic ionic plastic crystals. This compound has a solid–solid phase transition at 82 °C, and melts at 122 °C. A step increase in conductivity of about one order of magnitude is observed at the phase transition, followed by a decrease in activation energy for conduction. A large entropy gain occurs at the II → I transition, and 1H NMR linewidth measurements together with second moment calculations showed that the dimethylpyrrolidinium cation goes from a static state, to full isotropic tumbling. Raman measurements confirm that the cation as well as the anion exhibit increased rotational mobility when entering phase I.
JournalSolid state ionics
Pagination1798 - 1803
LocationAmsterdam, The Netherlands
Publication classificationC1.1 Refereed article in a scholarly journal
Copyright notice2008, Elsevier B.V.
Read the peer-reviewed publication
plastic crystalpyrrolidiniumthiocyanatephase transitionrotational motionsNMRramanScience & TechnologyPhysical SciencesChemistry, PhysicalPhysics, Condensed MatterChemistryPhysicsIONIC ASSOCIATIONELECTRICAL-CONDUCTIVITYAPROTIC-SOLVENTSROTATOR-PHASETHERMODYNAMIC PROPERTIESLITHIUM THIOCYANATEMAGNETIC-RESONANCEGLOBULAR MOLECULESHEAT CAPACITIESCRYSTAL