2018 |
Lodeiro, L; Contreras, R; Ormazabal-Toledo, R How Meaningful Is the Halogen Bonding in 1-Ethyl-3-Methyl Imidazolium-Based Ionic Liquids for Co2 Capture? Artículo de revista Journal of Physical Chemistry B, 122 (32), pp. 7907-7914, 2018, ISSN: 1520-6106. Resumen | Enlaces | BibTeX | Etiquetas: atmospheric carbon-dioxide, co2, conversion, dynamics, field, hydrogen-bonds, mechanism molecular-force reactivity, solubility, solvents @article{RN419, title = {How Meaningful Is the Halogen Bonding in 1-Ethyl-3-Methyl Imidazolium-Based Ionic Liquids for Co2 Capture?}, author = { L. Lodeiro and R. Contreras and R. Ormazabal-Toledo}, url = {/brokenurl#<Go to ISI>://WOS:000442437700011}, doi = {10.1021/acs.jpcb.8b04990}, issn = {1520-6106}, year = {2018}, date = {2018-01-01}, journal = {Journal of Physical Chemistry B}, volume = {122}, number = {32}, pages = {7907-7914}, abstract = {We report on several parameters that can be used to describe the 1-ethyl-3-methyl-4,5-(X-2)imidazolium cations (where X = H, Br, and I) within the Canongia-Lopez and Padua Force Field (CL&P) framework. Geometrical parameters like intramolecular distances and radial distribution functions are close to the experimental structure. Density values obtained with our force field are within the expected ones from CL&P calculations in related systems. This information is used to simulate through molecular dynamics the solubilization of CO2 by these ILs. For pure ILs, the addition of halides in position 4 and 5 promotes an enhanced hydrogen bond interaction at position 2 with the oxygen atoms in the anion. It is found that CO2 should be in the interstices of the anion-cation 3D network with longer distances than those found in other reports at ab initio levels, suggesting that halogen bond, if present, may be not the driving force interaction in these systems. Therefore, it seems that CO2 interacts linearly via an oxygen atom with the cation and with the anion through a pi-stacking or hydrogen-bonded fashions. Solvation enthalpies compare well with the experimental data, thereby suggesting that halogenated ILs dissolve more efficiently in CO2 than C(2)C(1)Im(+) derivatives. This result suggests that halogenated ILs can be considered as reliable candidates for CO2 capture.}, keywords = {atmospheric carbon-dioxide, co2, conversion, dynamics, field, hydrogen-bonds, mechanism molecular-force reactivity, solubility, solvents}, pubstate = {published}, tppubtype = {article} } We report on several parameters that can be used to describe the 1-ethyl-3-methyl-4,5-(X-2)imidazolium cations (where X = H, Br, and I) within the Canongia-Lopez and Padua Force Field (CL&P) framework. Geometrical parameters like intramolecular distances and radial distribution functions are close to the experimental structure. Density values obtained with our force field are within the expected ones from CL&P calculations in related systems. This information is used to simulate through molecular dynamics the solubilization of CO2 by these ILs. For pure ILs, the addition of halides in position 4 and 5 promotes an enhanced hydrogen bond interaction at position 2 with the oxygen atoms in the anion. It is found that CO2 should be in the interstices of the anion-cation 3D network with longer distances than those found in other reports at ab initio levels, suggesting that halogen bond, if present, may be not the driving force interaction in these systems. Therefore, it seems that CO2 interacts linearly via an oxygen atom with the cation and with the anion through a pi-stacking or hydrogen-bonded fashions. Solvation enthalpies compare well with the experimental data, thereby suggesting that halogenated ILs dissolve more efficiently in CO2 than C(2)C(1)Im(+) derivatives. This result suggests that halogenated ILs can be considered as reliable candidates for CO2 capture. |
2017 |
Orellana, C; Mendizabal, F; González, G; Miranda-Rojas, S; Barrientos-Poblete, L Palmitic Acid and Hexadecylamine Molecules Assdsorbed on Titania Surface in Hybrid Composites. Effect of Surfactants Using Density Functional Theory Artículo de revista Computational and Theoretical Chemistry, 1110 , pp. 50-59, 2017, ISSN: 2210-271x. Resumen | Enlaces | BibTeX | Etiquetas: basis-sets, bsse, calculations, catalysis, clusters, compounds, dft dft, dioxide dispersion enzymatic hexadecylamine, hydrogen-bonds, interactions, laminar n-body noncovalent palmitic photocatalysis properties, sensitized solar-cells, spectroscopic strong term, tio2, titanium @article{orellana2017palmitic, title = {Palmitic Acid and Hexadecylamine Molecules Assdsorbed on Titania Surface in Hybrid Composites. Effect of Surfactants Using Density Functional Theory}, author = { C. Orellana and F. Mendizabal and G. Gonz\'{a}lez and S. Miranda-Rojas and L. Barrientos-Poblete}, url = {/brokenurl#<Go to ISI>://WOS:000401679900007}, doi = {10.1016/j.comptc.2017.04.006}, issn = {2210-271x}, year = {2017}, date = {2017-01-01}, journal = {Computational and Theoretical Chemistry}, volume = {1110}, pages = {50-59}, publisher = {2017 Elsevier B.V.}, abstract = {A complete theoretical characterization of the factors involved in the stabilization of hybrid laminar composites is reported, with the purpose of understanding the main interactions involved in the formation of these types of systems. The models were built using two different surfactants: hexadecylamine (HDA) and palmitic acid (PAc), on a cluster of titania (TiO2) which represents its anatase crystalline phase. We explored the relevance of the titania-surfactant and surfactant-surfactant interactions, and of the protonation state of the palmitic acid in the stabilization of the hybrid laminar composites. The results were rationalized using energy decomposition analysis (EDA) and the non-covalent interaction index (NIC). The interaction energies between HDA and the TiO2 surface without the contribution of the dispersion forces were -25 kcal/mol and -29 kcal/mol for the (1 0 0) and (1 01) surfaces, respectively. These results suggest the formation of a donor-acceptor bond between HDA-TiO2 allowing its stabilization. On the other hand, the interaction energy between PAc and the TiO2 (1 0 1) surface was about -45 kcal/mol without the dispersion term. Thus, the PAc-TiO2 model has a higher covalent character than the HDA-TiO2 interaction, as confirmed by the energy decomposition analyses. The results suggest new hybrid laminar composites which are better when carboxylic acid was used instead of amines. Therefore, the use of surfactants with the carboxyl functional group yielded more stable TiO2 hybrid composites. The interaction energy between surfactant chains was about -13 kcal/mol, confirming the importance of dispersion forces in the stabilization of these types of systems. The study of systems with palmitic acid was complemented by building some anionic models to show the importance of acid protons in those systems. However, when the acidic hydrogens were removed, the interaction energy between the PAc molecules considering the dispersion correction increased to 45 kcal/mol, with a highly repulsive character. These results suggest that the acid hydrogens of the PAc surfactants play a fundamental role in terms of correctly representing the carboxylic acid-TiO2 interface and the stabilization of the laminar hybrid composites.}, keywords = {basis-sets, bsse, calculations, catalysis, clusters, compounds, dft dft, dioxide dispersion enzymatic hexadecylamine, hydrogen-bonds, interactions, laminar n-body noncovalent palmitic photocatalysis properties, sensitized solar-cells, spectroscopic strong term, tio2, titanium}, pubstate = {published}, tppubtype = {article} } A complete theoretical characterization of the factors involved in the stabilization of hybrid laminar composites is reported, with the purpose of understanding the main interactions involved in the formation of these types of systems. The models were built using two different surfactants: hexadecylamine (HDA) and palmitic acid (PAc), on a cluster of titania (TiO2) which represents its anatase crystalline phase. We explored the relevance of the titania-surfactant and surfactant-surfactant interactions, and of the protonation state of the palmitic acid in the stabilization of the hybrid laminar composites. The results were rationalized using energy decomposition analysis (EDA) and the non-covalent interaction index (NIC). The interaction energies between HDA and the TiO2 surface without the contribution of the dispersion forces were -25 kcal/mol and -29 kcal/mol for the (1 0 0) and (1 01) surfaces, respectively. These results suggest the formation of a donor-acceptor bond between HDA-TiO2 allowing its stabilization. On the other hand, the interaction energy between PAc and the TiO2 (1 0 1) surface was about -45 kcal/mol without the dispersion term. Thus, the PAc-TiO2 model has a higher covalent character than the HDA-TiO2 interaction, as confirmed by the energy decomposition analyses. The results suggest new hybrid laminar composites which are better when carboxylic acid was used instead of amines. Therefore, the use of surfactants with the carboxyl functional group yielded more stable TiO2 hybrid composites. The interaction energy between surfactant chains was about -13 kcal/mol, confirming the importance of dispersion forces in the stabilization of these types of systems. The study of systems with palmitic acid was complemented by building some anionic models to show the importance of acid protons in those systems. However, when the acidic hydrogens were removed, the interaction energy between the PAc molecules considering the dispersion correction increased to 45 kcal/mol, with a highly repulsive character. These results suggest that the acid hydrogens of the PAc surfactants play a fundamental role in terms of correctly representing the carboxylic acid-TiO2 interface and the stabilization of the laminar hybrid composites. |
2018 |
How Meaningful Is the Halogen Bonding in 1-Ethyl-3-Methyl Imidazolium-Based Ionic Liquids for Co2 Capture? Artículo de revista Journal of Physical Chemistry B, 122 (32), pp. 7907-7914, 2018, ISSN: 1520-6106. |
2017 |
Palmitic Acid and Hexadecylamine Molecules Assdsorbed on Titania Surface in Hybrid Composites. Effect of Surfactants Using Density Functional Theory Artículo de revista Computational and Theoretical Chemistry, 1110 , pp. 50-59, 2017, ISSN: 2210-271x. |