TY - JOUR
T1 - Spatial and thermal signatures of α and β relaxations in glassy and glacial aliphatic ionic liquids
AU - Lima, Thamires A.
AU - Li, Zhixia
AU - Tyagi, Madhusudan
AU - Ribeiro, Mauro C.C.
AU - Z, Y
N1 - T.A.L. is indebted to the fellowship provided by FAPESP (Grant Nos. 2016/24241-5 and 2012/13119-3). Part of this work (neutron scattering experiments) is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division, under Award No. DE-SC-0014084. Access to the HFBS was provided by Center for High Resolution, a partnership between the NIST and the NSF under agreement no. DMR-1508249. The identification of any commercial product or trade name does not imply endorsement or recommendation by the NIST.
PY - 2019/4/14
Y1 - 2019/4/14
N2 - The competition between Coulomb and van der Waals interactions brings forth unique dynamic features and broad applications to ionic liquids. Herein, we present a combined calorimetric, X-ray diffraction, incoherent elastic, and quasi-elastic neutron scattering study, over a wide temperature range (180-340 K), of the relaxational dynamics of the liquid, supercooled liquid, crystalline, glassy, and glacial states of two model ionic liquids: tributylmethylammonium (a good glass-former) and butyltrimethylammonium (a good crystal-former) cations and the bis(trifluoromethanesulfonyl)imide anion. In both systems, we observed two distinct relaxation processes. The Q-dependence of the respective relaxation time shows that the α-process is diffusive, while the β-process is modulated by the structure of the liquids.
AB - The competition between Coulomb and van der Waals interactions brings forth unique dynamic features and broad applications to ionic liquids. Herein, we present a combined calorimetric, X-ray diffraction, incoherent elastic, and quasi-elastic neutron scattering study, over a wide temperature range (180-340 K), of the relaxational dynamics of the liquid, supercooled liquid, crystalline, glassy, and glacial states of two model ionic liquids: tributylmethylammonium (a good glass-former) and butyltrimethylammonium (a good crystal-former) cations and the bis(trifluoromethanesulfonyl)imide anion. In both systems, we observed two distinct relaxation processes. The Q-dependence of the respective relaxation time shows that the α-process is diffusive, while the β-process is modulated by the structure of the liquids.
UR - https://www.scopus.com/pages/publications/85064198300
UR - https://www.scopus.com/pages/publications/85064198300#tab=citedBy
U2 - 10.1063/1.5081684
DO - 10.1063/1.5081684
M3 - Article
C2 - 30981243
AN - SCOPUS:85064198300
SN - 0021-9606
VL - 150
JO - Journal of Chemical Physics
JF - Journal of Chemical Physics
IS - 14
M1 - 144506
ER -