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. |
2015 |
Mendizabal, F; Miranda-Rojas, S; Barrientos-Poblete, L A Comparative Study between Post-Hartree-Fock Methods and Density Functional Theory in Closed-Shell Aurophilic Attraction Artículo de revista Computational and Theoretical Chemistry, 1057 , pp. 74-79, 2015, ISSN: 2210-271x. Resumen | Enlaces | BibTeX | Etiquetas: attraction, au, aurophilic chemistry, clusters, complexes, correction, crystal-structures, cu dft, dimers, dispersion gold interaction, kinetics, metallophilic theoretical thermochemical @article{RN254, title = {A Comparative Study between Post-Hartree-Fock Methods and Density Functional Theory in Closed-Shell Aurophilic Attraction}, author = { F. Mendizabal and S. Miranda-Rojas and L. Barrientos-Poblete}, url = {/brokenurl#<Go to ISI>://WOS:000352042300010}, doi = {10.1016/j.comptc.2015.01.021}, issn = {2210-271x}, year = {2015}, date = {2015-01-01}, journal = {Computational and Theoretical Chemistry}, volume = {1057}, pages = {74-79}, publisher = {2015 Elsevier B.V.}, abstract = {The inter- and intramolecular aurophilic [ClAuPH3](2), [S(AuPH3)(2)] and [AuPH3](4)(2+) interactions were studied using ab initio post-Hartree-Fock and DFT methodologies. The post-Hartree-Fock methods provide results closer to the experimental data than DFT-based methods. It is possible to highlight the results obtained by the SCS-MP2 and CCSD(T) methods. In the classic [ClAuPH3](2) dimer, the aurophilic interaction is driven by the induction and dispersion terms. When DFT is used, the best results of geometry and interaction energy are obtained with the PW91 level. We find -D3 Grimme correction, M06HF, M06L, M06 M062X, M052X, CAM-B3LYP and LC-omega PBE provided results of similar accuracy as MP2.}, keywords = {attraction, au, aurophilic chemistry, clusters, complexes, correction, crystal-structures, cu dft, dimers, dispersion gold interaction, kinetics, metallophilic theoretical thermochemical}, pubstate = {published}, tppubtype = {article} } The inter- and intramolecular aurophilic [ClAuPH3](2), [S(AuPH3)(2)] and [AuPH3](4)(2+) interactions were studied using ab initio post-Hartree-Fock and DFT methodologies. The post-Hartree-Fock methods provide results closer to the experimental data than DFT-based methods. It is possible to highlight the results obtained by the SCS-MP2 and CCSD(T) methods. In the classic [ClAuPH3](2) dimer, the aurophilic interaction is driven by the induction and dispersion terms. When DFT is used, the best results of geometry and interaction energy are obtained with the PW91 level. We find -D3 Grimme correction, M06HF, M06L, M06 M062X, M052X, CAM-B3LYP and LC-omega PBE provided results of similar accuracy as MP2. |
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. |
2015 |
A Comparative Study between Post-Hartree-Fock Methods and Density Functional Theory in Closed-Shell Aurophilic Attraction Artículo de revista Computational and Theoretical Chemistry, 1057 , pp. 74-79, 2015, ISSN: 2210-271x. |