| Texto completo | |
| Autor(es): |
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]
Número total de Autores: 7
|
| Afiliação do(s) autor(es): | [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
Número total de Afiliações: 6
|
| Tipo de documento: | Artigo Científico |
| Fonte: | JOURNAL OF MOLECULAR LIQUIDS; v. 340, OCT 15 2021. |
| Citações Web of Science: | 0 |
| Resumo | |
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) | |
| Processo FAPESP: | 16/21070-5 - Espectroscopia vibracional com resolução espacial |
| Beneficiário: | Mauro Carlos Costa Ribeiro |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |
| Processo FAPESP: | 19/00207-0 - Teoria do funcional da densidade aplicada a dinâmica vibracional de cristais de sistemas iônicos. |
| Beneficiário: | Vitor Hugo Paschoal |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |
| Processo FAPESP: | 17/12063-8 - Dinâmica molecular de não-equilíbrio de líquidos iônicos |
| Beneficiário: | Kalil Bernardino |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |