| Full text | |
| Author(s): |
Total Authors: 2
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| Affiliation: | [1] Univ Sao Paulo, Dept Quim Fundamental, Inst Quim, Lab Espectroscopia Mol, Av Prof Linea Prestes 748, BR-5508000 Sao Paulo, SP - Brazil
Total Affiliations: 1
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| Document type: | Journal article |
| Source: | JOURNAL OF MOLECULAR LIQUIDS; v. 322, JAN 15 2021. |
| Web of Science Citations: | 0 |
| Abstract | |
Melting of the ionic liquid choline acetate, {[}Chol]{[}Ac], at similar to 335 K is manifest in the differential scanning calorimetry (DSC) curve as a broad band covering similar to 30 K of temperature range. The events taking place in the pre-melting of {[}Chol]{[}Ac] are revealed by Raman spectroscopy and rheological measurements. The low-frequency range of the Raman spectrum exhibits changes in the intermolecular vibrational modes and the higher frequency range indicates conformational changes of the choline cation. Oscillatory rheological measurements show that the sample experiences a stiffening of its rheological characteristics within the temperature interval encompassing the melting process. Taking together the spectroscopic and rheological data, it is concluded that the sample experiences partial recrystallization during the pre-melting of {[}Chol]{[}Ac]. (C) 2020 Elsevier B.V. All rights reserved. (AU) | |
| FAPESP's process: | 17/23051-0 - Phase transitions, structure, and rheology of ionic liquids |
| Grantee: | Ícaro Francescato Tavares de Souza |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |
| FAPESP's process: | 16/21070-5 - Vibrational spectroscopy with spatial resolution |
| Grantee: | Mauro Carlos Costa Ribeiro |
| Support Opportunities: | Research Projects - Thematic Grants |