| Full text | |
| Author(s): |
Faria, Luiz F. O.
[1]
;
Paschoal, Vitor H.
[1]
;
Lima, Thamires A.
[1]
;
Ferreira, Fabio F.
[2]
;
Freitas, Rafael S.
[3]
;
Ribeiro, Mauro C. C.
[1]
Total Authors: 6
|
| Affiliation: | [1] Univ Sao Paulo, Dept Quim Fundamental, Inst Quim, Lab Espect Mol, Ave Prof Lineu Prestes 748, BR-05508000 Sao Paulo, SP - Brazil
[2] Univ Fed ABC, Ctr Ciancias Nat & Humanas, BR-09210580 Sao Paulo - Brazil
[3] Univ Sao Paulo, Inst Fis, BR-05314970 Sao Paulo, SP - Brazil
Total Affiliations: 3
|
| Document type: | Journal article |
| Source: | Journal of Physical Chemistry B; v. 121, n. 42, p. 9902-9909, OCT 26 2017. |
| Web of Science Citations: | 3 |
| Abstract | |
A local order disorder transition has been disclosed in the thermophysical behavior of the ionic liquid 1-benzyl-3-methylimidazolium dicyanamide, {[}Bzmim] {[}N-(CN)(2)], and its microscopic nature revealed by spectroscopic techniques. Differential scanning calorimetry and specific heat measurements show a thermal event of small enthalpy variation taking place in the range 250-260 K, which is not due to crystallization or melting. Molecular dynamic simulations and X-ray diffraction measurements have been used to discuss the segregation of domains in the liquid structure of {[}Bzmim]{[}N(CN)(2)] Raman and NMR spectroscopy measurements as a function of temperature indicate that the microscopic origin of the event observed in the calorimetric measurements comes from structural rearrangement involving the benzyl group. The results indicate that the characteristic structural heterogeneity allow for rearrangements within local domains implying the good glass-forming ability for the low viscosity ionic liquid {[}Bzmim] {[}N(CN)(2)]. This work sheds light on our understanding of the microscopic origin behind complex thermal behavior of ionic liquids. (AU) | |
| FAPESP's process: | 15/05803-0 - Ionic liquid structure under high pressure |
| Grantee: | Luiz Felipe de Oliveira Faria |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |
| FAPESP's process: | 12/13119-3 - Vibrational spectroscopy in condensed phases |
| Grantee: | Mauro Carlos Costa Ribeiro |
| Support Opportunities: | Research Projects - Thematic Grants |
| FAPESP's process: | 14/15049-8 - A Raman spectroscopy study of the glass transition of ionic liquids under high pressure. |
| Grantee: | Thamires Andrade Lima |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |