Liquid methanol confined within functionalized silica nanopores. 2. Solvation dynamics of coumarin 153
Equilibrium and dynamical characteristics pertaining to the solvation of the fluorescent probe coumarin 153 in liquid methanol confined within cylindrical silica pores are investigated using molecular dynamics techniques. Three kinds of pores are examined: (i) Soft hydrophobic cavities, in which wal...
| Autores principales: | , , |
|---|---|
| Publicado: |
2011
|
| Materias: | |
| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_15206106_v115_n44_p12859_Elola http://hdl.handle.net/20.500.12110/paper_15206106_v115_n44_p12859_Elola |
| Aporte de: |
| id |
paper:paper_15206106_v115_n44_p12859_Elola |
|---|---|
| record_format |
dspace |
| spelling |
paper:paper_15206106_v115_n44_p12859_Elola2023-06-08T16:19:05Z Liquid methanol confined within functionalized silica nanopores. 2. Solvation dynamics of coumarin 153 Elola, María Dolores Rodriguez, Javier Laria, Daniel Hector Hydrophilicity Hydrophobicity Liquids Methanol Molecular dynamics Nanopores Probes Silica Angular motions Bistables Bulk-like Coumarin 153 Dynamical characteristics Fluorescent probes Functionalized silica Hydrophilic pores Hydrophobic cavities Hydrophobic environment Hydroxyl groups Inhomogeneities Interface roughness Lennard-Jones type Liquid methanol Maximum amplitude Molecular dynamics techniques Molecular planes Oxygen site Polar groups Pore wall Silica pores Solid interfaces Solvation dynamics Solvation response Solvation shell Solvation state Solvation structure Spatial localization Trimethylsilyl Trimethylsilyl groups Vertical excitation Solvation Equilibrium and dynamical characteristics pertaining to the solvation of the fluorescent probe coumarin 153 in liquid methanol confined within cylindrical silica pores are investigated using molecular dynamics techniques. Three kinds of pores are examined: (i) Soft hydrophobic cavities, in which wall-solvent interactions were exclusively of the Lennard-Jones type; (ii) Hydrophilic cavities, in which unsaturated oxygen sites at the wall were transformed into hydroxyl groups; (iii) Rugged pores, in which 60% of the polar groups were transformed into bulkier and mobile trimethylsilyl moieties. Equilibrium solvation structures in the three pores differ considerably: In hydrophobic environments, the solute remains adsorbed to the pore wall, with its molecular plane mostly parallel to the interface. Upon hydroxylation, the solid interface becomes preferentially coated by methanol, leading to a bistable solvation state of the probe, with alternation of "wall-like" and "bulk-like" events. An increment in the interface roughness promotes a solvation structure characterized by the embedding of the probe within a wall domain surrounded by trimethylsilyl groups. In hydrophobic environments, the relevant dynamical modes of the probe can be cast in terms of in-the-wall rotations, whereas in hydrophilic pores, out-of-the-wall evolutions are also present. The embedding of the probe at wall domains in more rugged pores, leads to restrained angular motions, with maximum amplitudes of the order of 20°. Results of early stages of the solvation response of the environment following a vertical excitation of the probe are also presented. During the initial 30 ps, we found no evidence of modifications in the spatial localizations of the probe. The overall responses are found to be between 2 and 4.5 times slower than the one observed in the bulk, being the fastest relaxation the one associated to rugged pores whereas the slowest one corresponds to hydrophilic cavities. These features are rationalized in terms of the composition of the first solvation shells and the local dynamical inhomogeneities prevailing within the different regions of the pores. © 2011 American Chemical Society. Fil:Elola, M.D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Rodriguez, J. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Laria, D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2011 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_15206106_v115_n44_p12859_Elola http://hdl.handle.net/20.500.12110/paper_15206106_v115_n44_p12859_Elola |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Hydrophilicity Hydrophobicity Liquids Methanol Molecular dynamics Nanopores Probes Silica Angular motions Bistables Bulk-like Coumarin 153 Dynamical characteristics Fluorescent probes Functionalized silica Hydrophilic pores Hydrophobic cavities Hydrophobic environment Hydroxyl groups Inhomogeneities Interface roughness Lennard-Jones type Liquid methanol Maximum amplitude Molecular dynamics techniques Molecular planes Oxygen site Polar groups Pore wall Silica pores Solid interfaces Solvation dynamics Solvation response Solvation shell Solvation state Solvation structure Spatial localization Trimethylsilyl Trimethylsilyl groups Vertical excitation Solvation |
| spellingShingle |
Hydrophilicity Hydrophobicity Liquids Methanol Molecular dynamics Nanopores Probes Silica Angular motions Bistables Bulk-like Coumarin 153 Dynamical characteristics Fluorescent probes Functionalized silica Hydrophilic pores Hydrophobic cavities Hydrophobic environment Hydroxyl groups Inhomogeneities Interface roughness Lennard-Jones type Liquid methanol Maximum amplitude Molecular dynamics techniques Molecular planes Oxygen site Polar groups Pore wall Silica pores Solid interfaces Solvation dynamics Solvation response Solvation shell Solvation state Solvation structure Spatial localization Trimethylsilyl Trimethylsilyl groups Vertical excitation Solvation Elola, María Dolores Rodriguez, Javier Laria, Daniel Hector Liquid methanol confined within functionalized silica nanopores. 2. Solvation dynamics of coumarin 153 |
| topic_facet |
Hydrophilicity Hydrophobicity Liquids Methanol Molecular dynamics Nanopores Probes Silica Angular motions Bistables Bulk-like Coumarin 153 Dynamical characteristics Fluorescent probes Functionalized silica Hydrophilic pores Hydrophobic cavities Hydrophobic environment Hydroxyl groups Inhomogeneities Interface roughness Lennard-Jones type Liquid methanol Maximum amplitude Molecular dynamics techniques Molecular planes Oxygen site Polar groups Pore wall Silica pores Solid interfaces Solvation dynamics Solvation response Solvation shell Solvation state Solvation structure Spatial localization Trimethylsilyl Trimethylsilyl groups Vertical excitation Solvation |
| description |
Equilibrium and dynamical characteristics pertaining to the solvation of the fluorescent probe coumarin 153 in liquid methanol confined within cylindrical silica pores are investigated using molecular dynamics techniques. Three kinds of pores are examined: (i) Soft hydrophobic cavities, in which wall-solvent interactions were exclusively of the Lennard-Jones type; (ii) Hydrophilic cavities, in which unsaturated oxygen sites at the wall were transformed into hydroxyl groups; (iii) Rugged pores, in which 60% of the polar groups were transformed into bulkier and mobile trimethylsilyl moieties. Equilibrium solvation structures in the three pores differ considerably: In hydrophobic environments, the solute remains adsorbed to the pore wall, with its molecular plane mostly parallel to the interface. Upon hydroxylation, the solid interface becomes preferentially coated by methanol, leading to a bistable solvation state of the probe, with alternation of "wall-like" and "bulk-like" events. An increment in the interface roughness promotes a solvation structure characterized by the embedding of the probe within a wall domain surrounded by trimethylsilyl groups. In hydrophobic environments, the relevant dynamical modes of the probe can be cast in terms of in-the-wall rotations, whereas in hydrophilic pores, out-of-the-wall evolutions are also present. The embedding of the probe at wall domains in more rugged pores, leads to restrained angular motions, with maximum amplitudes of the order of 20°. Results of early stages of the solvation response of the environment following a vertical excitation of the probe are also presented. During the initial 30 ps, we found no evidence of modifications in the spatial localizations of the probe. The overall responses are found to be between 2 and 4.5 times slower than the one observed in the bulk, being the fastest relaxation the one associated to rugged pores whereas the slowest one corresponds to hydrophilic cavities. These features are rationalized in terms of the composition of the first solvation shells and the local dynamical inhomogeneities prevailing within the different regions of the pores. © 2011 American Chemical Society. |
| author |
Elola, María Dolores Rodriguez, Javier Laria, Daniel Hector |
| author_facet |
Elola, María Dolores Rodriguez, Javier Laria, Daniel Hector |
| author_sort |
Elola, María Dolores |
| title |
Liquid methanol confined within functionalized silica nanopores. 2. Solvation dynamics of coumarin 153 |
| title_short |
Liquid methanol confined within functionalized silica nanopores. 2. Solvation dynamics of coumarin 153 |
| title_full |
Liquid methanol confined within functionalized silica nanopores. 2. Solvation dynamics of coumarin 153 |
| title_fullStr |
Liquid methanol confined within functionalized silica nanopores. 2. Solvation dynamics of coumarin 153 |
| title_full_unstemmed |
Liquid methanol confined within functionalized silica nanopores. 2. Solvation dynamics of coumarin 153 |
| title_sort |
liquid methanol confined within functionalized silica nanopores. 2. solvation dynamics of coumarin 153 |
| publishDate |
2011 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_15206106_v115_n44_p12859_Elola http://hdl.handle.net/20.500.12110/paper_15206106_v115_n44_p12859_Elola |
| work_keys_str_mv |
AT elolamariadolores liquidmethanolconfinedwithinfunctionalizedsilicananopores2solvationdynamicsofcoumarin153 AT rodriguezjavier liquidmethanolconfinedwithinfunctionalizedsilicananopores2solvationdynamicsofcoumarin153 AT lariadanielhector liquidmethanolconfinedwithinfunctionalizedsilicananopores2solvationdynamicsofcoumarin153 |
| _version_ |
1768542284228329472 |