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Title: Alkyl Chain Length and Temperature Effects on Structural Properties of Pyrrolidinium-Based Ionic Liquids: A Combined Atomistic Simulation and Small-Angle X-ray Scattering Study.

Molecular dynamics (MD) simulations of 1-alkyl-1-methylpyrrolidinium 12 bis(trifluoromethanesulfonyl)imide ([CnMPy][Tf2N], n = 3, 4, 6, 8, 10) were conducted 13 using an all-atom model. Radial distribution functions (RDF) were computed and structure 14 functions were generated to compare with new X-ray scattering experimental results, 15 reported herein. The scattering peaks in the structure functions generally shift to lower Q 16 values with increased temperature for all the liquids in this series. However, the first sharp 17 diffraction peak (FSDP) in the longer alkyl chain liquids displays a marked shift to higher Q 18 values with increasing temperature. Alkyl chain-dependent ordering of the polar groups and 19 increased tail aggregation with increasing alkyl chain length were observed in the partial pair 20 correlation functions and the structure functions. The reasons for the observed alkyl chain- 21 dependent phenomena and temperature effects were explored.
Authors:
 [1] ;  [1] ;  [1] ;  [2] ;  [1] ;  [1] ;  [1] ;  [1] ;  [1] ;  [1]
  1. ORNL
  2. {Larry} M [ORNL
Publication Date:
OSTI Identifier:
1033171
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physical Chemistry Letters; Journal Volume: 3; Journal Issue: 1
Research Org:
Oak Ridge National Laboratory (ORNL)
Sponsoring Org:
SC USDOE - Office of Science (SC)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CHAINS; CORRELATION FUNCTIONS; DIFFRACTION; MOLTEN SALTS; SCATTERING; SIMULATION; SPATIAL DISTRIBUTION; STRUCTURE FUNCTIONS; TEMPERATURE DEPENDENCE