Density functional theory applyed to vibrational dynamics of crystals of ionic sys...
Vibrational Spectroscopy and Thermodynamic Properties of Ionic Liquids under High ...
Ab initio molecular dynamics of ionic liquids under pressure
| Full text | |
| Author(s): |
de Souza, Icaro F. T.
[1]
;
Paschoal, Vitor H.
[1]
;
Bernardino, Kalil
[1]
;
Lima, Thamires A.
[2, 1, 3]
;
Daemen, Luke L.
[4]
;
Y., Z.
[2, 5, 6]
;
Ribeiro, Mauro C. C.
[1]
Total Authors: 7
|
| Affiliation: | [1] Univ Sao Paulo, Inst Quim, Dept Quim Fundamental, Lab Espectroscopia Mol, BR-05513970 Sao Paulo, SP - Brazil
[2] Univ Illinois, Beckman Inst Adv Sci & Technol, Urbana, IL 61801 - USA
[3] Drexel Univ, Chem & Biol Engn Dept, Philadelphia, PA 19104 - USA
[4] Oak Ridge Natl Lab, Neutron Scattering Div, Oak Ridge, TN 37831 - USA
[5] Univ Illinois, Dept Nucl Plasma & Radiol Engn, Urbana, IL 61801 - USA
[6] Univ Illinois, Dept Elect & Comp Engn, Urbana, IL 61801 - USA
Total Affiliations: 6
|
| Document type: | Journal article |
| Source: | JOURNAL OF MOLECULAR LIQUIDS; v. 340, OCT 15 2021. |
| Web of Science Citations: | 0 |
| Abstract | |
The structure of choline salts containing the anions acetate, {[}Chol]{[}Ac], and dihydrogen phosphate, {[}Chol] {[}DHP], were investigated by infrared, Raman, and inelastic neutron scattering (INS). The chosen systems allow for the comparison of structural effects related to the bond acceptor characteristic of {[}Ac] and the simultaneous acceptor and donor characteristics of {[}DHP] in forming hydrogen bonds (H-bond) in salts of {[}Chol], which is itself prone to forming H-bonds. Different computational tools were used for the analysis of different spectral ranges. The calculation of the low-frequency range of Raman and INS spectra of the crystalline phases at low-temperatures by solid state DFPT (density functional perturbation theory) unveils the coupling between vibrations of the H-bonds and intramolecular modes. Changes observed in the spectral pattern of lattice and {[}DHP] modes upon heating crystalline {[}Chol]{[}DHP] are analogous to the ferroelectric-paraelectric phase transition known in the potassium salt of {[}DHP]. The fingerprint region of the vibrational spectra provides information concerning the {[}Chol] conformation in the solid phase (gauche in {[}Chol]{[}Ac] and anti in {[}Chol]{[}DHP]) and in aqueous solution. DFT calculations of ionic pairs and ionic clusters unveil the interplay between {[}Chol] conformation and the {[}DHP] ability to form H-bonded dimers of anions. The high-frequency spectral range and the structures driven by H-bonds are discussed using classical molecular dynamics (MD) simulations. The MD simulations of aqueous solutions highlight the strong anion-cation H-bond in {[}Chol]{[}Ac], in contrast to the strong anion-anion H-bond in {[}Chol]{[}DHP] due to occurrence of dimers and larger clusters of {[}DHP]. (c) 2021 Elsevier B.V. All rights reserved. (AU) | |
| FAPESP's process: | 16/21070-5 - Vibrational spectroscopy with spatial resolution |
| Grantee: | Mauro Carlos Costa Ribeiro |
| Support Opportunities: | Research Projects - Thematic Grants |
| FAPESP's process: | 19/00207-0 - Density functional theory applyed to vibrational dynamics of crystals of ionic systems. |
| Grantee: | Vitor Hugo Paschoal |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |
| FAPESP's process: | 17/12063-8 - Non-equilibrium molecular dynamics of ionic liquids |
| Grantee: | Kalil Bernardino |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |