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Senanayake HS, Greathouse JA, Thompson WH. Probing electrolyte–silica interactions through simulations of the infrared spectroscopy of nanoscale pores. J Chem Phys 2022; 157:034702. [DOI: 10.1063/5.0100583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The structural and dynamical properties of nanoconfined solutions can differ dramatically from those of the corresponding bulk systems. Understanding the changes induced by confinement is central to controlling the behavior of synthetic nanostructured materials and predicting the characteristics of biological and geochemical systems. A key outstanding issue is how the molecular-level behavior of nanoconfined electrolyte solutions is reflected in different experimental, particularly spectroscopic, measurements. This is addressed here through molecular dynamics simulations of the OH stretching infrared (IR) spectroscopy of NaCl, NaBr, and NaI solutions in isotopically dilute HOD/D2O confined in hydroxylated amorphous silica slit pores of width 1–6 nm and pH [Formula: see text]. In addition, the water reorientation dynamics and spectral diffusion, accessible by pump–probe anisotropy and two-dimensional IR measurements, are investigated. The aim is to elucidate the effect of salt identity, confinement, and salt concentration on the vibrational spectra. It is found that the IR spectra of the electrolyte solutions are only modestly blue-shifted upon confinement in amorphous silica slit pores, with both the size of the shift and linewidth increasing with the halide size, but these effects are suppressed as the salt concentration is increased. This indicates the limitations of linear IR spectroscopy as a probe of confined water. However, the OH reorientational and spectral diffusion dynamics are significantly slowed by confinement even at the lowest concentrations. The retardation of the dynamics eases with increasing salt concentration and pore width, but it exhibits a more complex behavior as a function of halide.
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Affiliation(s)
| | - Jeffery A. Greathouse
- Geochemistry Department, Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - Ward H. Thompson
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, USA
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Stogiannidis G, Tsigoias S, Mpourazanis P, Boghosian S, Kaziannis S, Kalampounias A. Dynamics and vibrational coupling of methyl acetate dissolved in ethanol. Chem Phys 2019. [DOI: 10.1016/j.chemphys.2019.02.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Affiliation(s)
- Ward H. Thompson
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, USA
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Burris PC, Laage D, Thompson WH. Simulations of the infrared, Raman, and 2D-IR photon echo spectra of water in nanoscale silica pores. J Chem Phys 2016; 144:194709. [DOI: 10.1063/1.4949766] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Paul C. Burris
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, USA
| | - Damien Laage
- Département de Chimie, Ecole Normale Supérieure-PSL Research University, Sorbonne Universités-UPMC Univ Paris 06, CNRS UMR 8640 PASTEUR, 24 rue Lhomond, 75005 Paris, France
| | - Ward H. Thompson
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, USA
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Wells RH, Thompson WH. What Determines the Location of a Small Solute in a Nanoconfined Liquid? J Phys Chem B 2015; 119:12446-54. [DOI: 10.1021/acs.jpcb.5b04770] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Robert H. Wells
- Department
of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Ward H. Thompson
- Department
of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
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Thompson WH. Structure, dynamics and hydrogen bonding of acetonitrile in nanoscale silica pores. MOLECULAR SIMULATION 2014. [DOI: 10.1080/08927022.2014.926550] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Norton CD, Thompson WH. Reorientation Dynamics of Nanoconfined Acetonitrile: A Critical Examination of Two-State Models. J Phys Chem B 2014; 118:8227-35. [DOI: 10.1021/jp501363q] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Cassandra D. Norton
- Department
of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Ward H. Thompson
- Department
of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
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Vartia AA, Thompson WH. Solvation and Spectra of a Charge Transfer Solute in Ethanol Confined within Nanoscale Silica Pores. J Phys Chem B 2012; 116:5414-24. [DOI: 10.1021/jp210737c] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Anthony A. Vartia
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Ward H. Thompson
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
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9
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Morales CM, Thompson WH. Molecular-level mechanisms of vibrational frequency shifts in a polar liquid. J Phys Chem B 2011; 115:7597-605. [PMID: 21608988 DOI: 10.1021/jp201591c] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A molecular-level analysis of the origins of the vibrational frequency shifts of the CN stretching mode in neat liquid acetonitrile is presented. The frequency shifts and infrared spectrum are calculated using a perturbation theory approach within a molecular dynamics simulation and are in good agreement with measured values reported in the literature. The resulting instantaneous frequency of each nitrile group is decomposed into the contributions from each molecule in the liquid and by interaction type. This provides a detailed picture of the mechanisms of frequency shifts, including the number of surrounding molecules that contribute to the shift, the relationship between their position and relative contribution, and the roles of electrostatic and van der Waals interactions. These results provide insight into what information is contained in infrared (IR) and Raman spectra about the environment of the probed vibrational mode.
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Affiliation(s)
- Christine M Morales
- Department of Chemistry, University of Wisconsin-Eau Claire, Eau Claire, Wisconsin 54702, USA
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Abstract
ABSTRACTAn overview of several NMR studies of liquids in confined geometries is
presented. First, the NMR relaxation rates, 1/T1,
1/T1ρ , and 1/T2 were measured for several
molecular liquids confined to porous silica glasses with pore radii in the
range from 12 Å to 100 Å as a function of temperature, pore size, and
frequency. The experimental relaxation data were interpreted in terms of
bulk, surface, and topological contributions using the following
expression:where 1/Tib and 1/Tis are the bulk and the surface
layer relaxation rates, ε is the thickness of the surface layer, R is the
pore radius, and Ai(ω) represents the pure topological
effect.Second, the pressure effects on the dynamics of the confined liquid of
acetonitrile-d3 were also investigated. Third, the natural
abundance of 13C spin lattice relaxation rates for CS2
confined to porous silica glasses provided information about confinement
effects on the angular momentum behavior of this simple liquid.
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11
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Elola MD, Rodriguez J, Laria D. Structure and dynamics of liquid methanol confined within functionalized silica nanopores. J Chem Phys 2010; 133:154707. [DOI: 10.1063/1.3503886] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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Shen S, Sun P, Li W, Parikh AN, Hu D. Substituent-dominated structure evolution during sol-gel synthesis: a comparative study of sol-gel processing of 3-glycidoxypropyltrimethoxysilane and methacryloxypropyltrimethoxysilane. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:7708-7716. [PMID: 20443541 DOI: 10.1021/la904040c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The sol-gel processes of 3-glycidoxypropyltrimethoxysilane (GPTMS) and methacryloxypropyltrimethoxysilane (MAPTMS) have been followed by fluorescence spectroscopy with pyranine as a photophysical probe. The experimental results showed that this probe is sensitive to the structural evolution and microenvironment polarity. The specific comparison of the structural evolution in two substituted organotrialkoxysilanes, namely, MAPTMS and GPTMS, illustrates the ability of the substituents to interact with the microenvironment via electrostatic interactions. Interestingly, these interactions determine the kinds of intermediate supramolecular structures that form during the sol-gel process and hence control the structure of the ensuing sol-gel end product. In particular, the amphiphile-like character of the MAPTMS intermediates contrasts with the biamphiphilic character of their GPTMS counterparts, driving distinctly different transient and local molecular organizations, which in turn modulate the hydrolysis and condensation reactions during the sol-gel process.
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Affiliation(s)
- Shukun Shen
- School of Chemistry and Materials Science, Shaanxi Normal University, Xi'an 710062, People's Republic of China
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Gulmen TS, Thompson WH. Grand canonical Monte Carlo simulations of acetonitrile filling of silica pores of varying hydrophilicity/hydrophobicity. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:1103-1111. [PMID: 19113811 DOI: 10.1021/la801896g] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Grand canonical Monte Carlo simulations have been used to determine the equilibrium density of acetonitrile in model amorphous silica pores with varying radius and surface chemistry. Pores of diameter approximately 2-4 nm were considered with different ratios of surface -OH moieties to -OC(CH(3))(3) groups. The calculations found that the acetonitrile density in the interior of all the pores is essentially identical with that of the bulk liquid. On the other hand, a slightly elevated liquid density is observed near the pore surface for pores with only -OH surface moieties. Replacement of surface -OH groups with -OC(CH(3))(3) units lengthens the liquid/pore interfacial region as acetonitrile molecules can insert themselves between the -OC(CH(3))(3) units. The results indicate that the major effect of changing the surface functionality comes from the differences in excluded volume rather than hydrogen-bonding effects. Finally, the choice of the acetonitrile potential can qualitatively change the results.
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Affiliation(s)
- Tolga S Gulmen
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, USA
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Morales CM, Thompson WH. Simulations of Infrared Spectra of Nanoconfined Liquids: Acetonitrile Confined in Nanoscale, Hydrophilic Silica Pores. J Phys Chem A 2008; 113:1922-33. [DOI: 10.1021/jp8072969] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
| | - Ward H. Thompson
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045
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Morales CM, Thompson WH. Umbrella sampling of solute vibrational line shifts in mixed quantum-classical molecular dynamics simulations. J Phys Chem B 2008; 112:313-20. [PMID: 18081335 DOI: 10.1021/jp075038d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An umbrella sampling approach for vibrational frequency line shifts is presented. The technique allows for efficient sampling of the solvent configurations corresponding to frequency shifts of a solute in mixed quantum-classical simulations. The approach is generally applicable and can also be used within traditional perturbation theory calculations of frequency shifts. It is particularly useful in the extraction of detailed mechanistic information about the solute-solvent interactions giving rise to the frequency shifts. The method is illustrated by application to the simple I2 in a liquid Xe system, and the advantages are discussed.
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Yashonath S, Ghorai PK. Diffusion in Nanoporous Phases: Size Dependence and Levitation Effect. J Phys Chem B 2007; 112:665-86. [DOI: 10.1021/jp076031z] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- S. Yashonath
- Solid State and Structural Chemistry Unit, Center for Condensed Matter Theory, Indian Institute of Science, Bangalore-560012, India
| | - Pradip Kr. Ghorai
- Solid State and Structural Chemistry Unit, Center for Condensed Matter Theory, Indian Institute of Science, Bangalore-560012, India
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Morales CM, Thompson WH. Mixed Quantum-Classical Molecular Dynamics Analysis of the Molecular-Level Mechanisms of Vibrational Frequency Shifts. J Phys Chem A 2007; 111:5422-33. [PMID: 17580980 DOI: 10.1021/jp071656i] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A detailed analysis of the origins of vibrational frequency shifts of diatomic molecules (I2 and ICl) in a rare gas (Xe) liquid is presented. Specifically, vibrationally adiabatic mixed quantum-classical molecular dynamics simulations are used to obtain the instantaneous frequency shifts and correlate the shifts to solvent configurations. With this approach, important mechanistic questions are addressed, including the following: How many solvent atoms determine the frequency shift? What solvent atom configurations lead to blue shifts, and which lead to red shifts? What is the effect of solute asymmetry? The mechanistic analysis can be generally applied and should be useful in understanding what information is provided by infrared and Raman spectra about the environment of the probed vibrational mode.
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Gulmen TS, Thompson WH. Testing a two-state model of nanoconfined liquids: conformational equilibrium of ethylene glycol in amorphous silica pores. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2006; 22:10919-23. [PMID: 17154565 DOI: 10.1021/la062285k] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Molecular dynamics simulations of the conformational equilibrium of ethylene glycol in roughly cylindrical nanoscale amorphous silica pores are presented and analyzed in the context of a two-state model of confined liquids. This model assumes that an observable property of a confined liquid can be decomposed into a weighted average arising from two subensembles with distinct physical attributes: molecules at the surface and molecules in the interior of the pore. It is further assumed that the molecules in the interior exhibit behavior that is indistinguishable from that of the bulk liquid. However, the present simulation results are not consistent with this two-state model. Neither the assumption of two distinct subensembles nor the assumption that the interior molecules possess bulk-like behavior is supported.
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Affiliation(s)
- Tolga S Gulmen
- Department of Chemistry, University of Kansas, Lawrence, KS 66045, USA
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Massari AM, Finkelstein IJ, Fayer MD. Dynamics of proteins encapsulated in silica sol-gel glasses studied with IR vibrational echo spectroscopy. J Am Chem Soc 2006; 128:3990-7. [PMID: 16551107 PMCID: PMC2532503 DOI: 10.1021/ja058745y] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Spectrally resolved infrared stimulated vibrational echo spectroscopy is used to measure the fast dynamics of heme-bound CO in carbonmonoxy-myoglobin (MbCO) and -hemoglobin (HbCO) embedded in silica sol-gel glasses. On the time scale of approximately 100 fs to several picoseconds, the vibrational dephasing of the heme-bound CO is measurably slower for both MbCO and HbCO relative to that of aqueous protein solutions. The fast structural dynamics of MbCO, as sensed by the heme-bound CO, are influenced more by the sol-gel environment than those of HbCO. Longer time scale structural dynamics (tens of picoseconds), as measured by the extent of spectral diffusion, are the same for both proteins encapsulated in sol-gel glasses compared to that in aqueous solutions. A comparison of the sol-gel experimental results to viscosity-dependent vibrational echo data taken on various mixtures of water and fructose shows that the sol-gel-encapsulated MbCO exhibits dynamics that are the equivalent of the protein in a solution that is nearly 20 times more viscous than bulk water. In contrast, the HbCO dephasing in the sol-gel reflects only a 2-fold increase in viscosity. Attempts to alter the encapsulating pore size by varying the molar ratio of silane precursor to water (R value) used to prepare the sol-gel glasses were found to have no effect on the fast or steady-state spectroscopic results. The vibrational echo data are discussed in the context of solvent confinement and protein-pore wall interactions to provide insights into the influence of a confined environment on the fast structural dynamics experienced by a biomolecule.
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Hu D, Croutxé-Barghorn C, Feuillade M, Carré C. Fluorescence Study of the Sol−Gel Process in Hybrid Precursors: Evidence of Concentration Fluctuations at the Local Scale. J Phys Chem B 2005; 109:15214-20. [PMID: 16852926 DOI: 10.1021/jp050208c] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Hybrid sol-gel materials have been prepared by hydrolytic polycondensation of an alkoxysilane. The sol-gel process of methacryloxypropyltrimethoxysilane (MAPTMS) has been followed by fluorescence spectroscopy with 2-naphthol as a probe. The experimental results showed that this photoprobe was dramatically sensitive to the microenvironment polarity. Spectroscopic studies revealed fluctuations of the maximum emission intensity and wavelength as a function of time. These fluctuations were attributed to the amphiphilic behavior of the hydrolyzed precursor. The maximum emission wavelength of the probe corresponding to its protonated form was higher than in pure water. All the results suggest that the presence of water molecules, tightly bonded to the polar head of the silanols, increased locally the sol polarity and induced a red-shifted emission. Fluorescence spectroscopy emphasized the reversibility of monomeric silanol aggregates and the changes in hydroxy group number of the silica network during the sol maturation. The behavior of this system upon shaking confirmed this statement.
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Affiliation(s)
- Daodao Hu
- School of Chemistry and Material Science, Shaanxi Normal University, Xi'an 710062, People's Republic of China
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21
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Kanungo M, Collinson MM. Controlling diffusion in sol-gel derived monoliths. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:827-829. [PMID: 15667155 DOI: 10.1021/la047518r] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Redox probes were trapped within a silica monolith prepared in part with organoalkoxysilanes containing a quaternary ammonium functional group. The diffusion coefficients of the entrapped molecules were measured as the gels were slowly dried using chronoamperometry and cyclic voltammetry with ultramicroelectrodes. Gel-entrapped cobalt(II) tris(bipyridine) (Co(bpy)(3)(2+)) diffuses at rates similar to that measured in the sols by incorporating a small amount of the positively charged functional group in the matrix. In comparison, the diffusion coefficient of gel-entrapped ferricyanide (Fe(CN)(6)(3-)) drops an order of magnitude relative to its value in the sol soon after gelation. These results demonstrate the ease at which diffusion in hydrated gels can be easily controlled by simply changing the charge on the walls of the silica host.
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Affiliation(s)
- Mandakini Kanungo
- Department of Chemistry, Kansas State University, Manhattan, KS 66506-3701, USA
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Walcarius A, Mandler D, Cox JA, Collinson M, Lev O. Exciting new directions in the intersection of functionalized sol–gel materials with electrochemistry. ACTA ACUST UNITED AC 2005. [DOI: 10.1039/b504839g] [Citation(s) in RCA: 242] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Farrer RA, Fourkas JT. Orientational dynamics of liquids confined in nanoporous sol-gel glasses studied by optical kerr effect spectroscopy. Acc Chem Res 2003; 36:605-12. [PMID: 12924957 DOI: 10.1021/ar0200302] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
When a liquid is restricted to volumes on a molecular distance scale, its orientational and translational dynamics are perturbed strongly by the confinement. Nanoporous sol-gel glasses are an excellent model system for studying the effects of confinement on the behavior of liquids, and in this Account we review experiments in which ultrafast optical Kerr effect spectroscopy has been used to study the orientational dynamics of liquids confined in these media. We contrast the effects of confinement on the orientational dynamics of weakly wetting, strongly wetting, and networked liquids, and we discuss the influence of factors such as pore size, molecular shape, and surface chemistry.
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Affiliation(s)
- Richard A Farrer
- Eugene F Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, USA
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Kalampounias A, Kirillov S, Steffen W, Yannopoulos S. Raman spectra and microscopic dynamics of bulk and confined salol. J Mol Struct 2003. [DOI: 10.1016/s0022-2860(03)00128-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Kalampounias AG, Yannopoulos SN, Steffen W, Kirillova LI, Kirillov SA. Short-time dynamics of glass-forming liquids: Phenyl salicylate (salol) in bulk liquid, dilute solution, and confining geometries. J Chem Phys 2003. [DOI: 10.1063/1.1565325] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Shustak G, Marx S, Turyan I, Mandler D. Application of Sol-Gel Technology for Electroanalytical Sensing. ELECTROANAL 2003. [DOI: 10.1002/elan.200390046] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Baumann R, Ferrante C, Kneuper E, Deeg FW, Bräuchle C. Influence of Confinement on the Solvation and Rotational Dynamics of Coumarin 153 in Ethanol. J Phys Chem A 2003. [DOI: 10.1021/jp027172y] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Robert Baumann
- Department Chemie, Bereich Physikalische Chemie, Ludwig-Maximilians- Universität, Butenandtstrasse 5-13, D-81377 München, Germany
| | - Camilla Ferrante
- Department Chemie, Bereich Physikalische Chemie, Ludwig-Maximilians- Universität, Butenandtstrasse 5-13, D-81377 München, Germany
| | - Erwin Kneuper
- Department Chemie, Bereich Physikalische Chemie, Ludwig-Maximilians- Universität, Butenandtstrasse 5-13, D-81377 München, Germany
| | - Fred-Walter Deeg
- Department Chemie, Bereich Physikalische Chemie, Ludwig-Maximilians- Universität, Butenandtstrasse 5-13, D-81377 München, Germany
| | - Christoph Bräuchle
- Department Chemie, Bereich Physikalische Chemie, Ludwig-Maximilians- Universität, Butenandtstrasse 5-13, D-81377 München, Germany
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Baumann R, Ferrante C, Deeg FW, Bräuchle C. Solvation dynamics of nile blue in ethanol confined in porous sol–gel glasses. J Chem Phys 2001. [DOI: 10.1063/1.1309151] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Crupi V, Majolino D, Migliardo P, Venuti V. Diffusive Relaxations and Vibrational Properties of Water and H-bonded Systems in Confined State by Neutrons and Light Scattering: State of the Art. J Phys Chem A 2000. [DOI: 10.1021/jp001736l] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Vincenza Crupi
- Department of Physics, Messina University and INFM Section of Messina, C.da Papardo, S.ta Sperone 31, P.O. Box 55, 98166 S. Agata, Messina, Italy
| | - Domenico Majolino
- Department of Physics, Messina University and INFM Section of Messina, C.da Papardo, S.ta Sperone 31, P.O. Box 55, 98166 S. Agata, Messina, Italy
| | - Placido Migliardo
- Department of Physics, Messina University and INFM Section of Messina, C.da Papardo, S.ta Sperone 31, P.O. Box 55, 98166 S. Agata, Messina, Italy
| | - Valentina Venuti
- Department of Physics, Messina University and INFM Section of Messina, C.da Papardo, S.ta Sperone 31, P.O. Box 55, 98166 S. Agata, Messina, Italy
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Electrochemiluminescence of ruthenium (II) tris(bipyridine) encapsulated in sol-gel glasses. Anal Chem 2000; 72:2914-8. [PMID: 10905327 DOI: 10.1021/ac9913208] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The electrogenerated chemiluminescence (ECL) of Ru(bpy)3 2+ and tripropylamine, tributylamine, triethylamine, trimethylamine, or sodium oxalate encapsulated within sol-gel-derived silica monoliths have been investigated using an immobilized ultramicroelectrode assembly. The major purpose of this study was to investigate the role of the reductant on the magnitude and stability of the ECL in this solid host matrix. For gel-entrapped Ru(bpy)3 2-/tertiary amines, the shape and intensity of the ECL-potential curves were highly dependent on scan rate. At 10 mV/s, the ECL intensity was ca. 6-fold higher relative to that observed at 500 mV/s. When the ECL acquired at low scan rates was normalized by that obtained in solution under similar conditions, a value of 0.03-0.06 was obtained. In direct contrast, the ECL of the Ru(bpy)3 2+-oxalate system showed little dependence on scan rate, and the ECL was ca. 65-75% of that measured in solution. These differences can be attributed to differences in rotational and translational mobility between the reductants (amines vs oxalate) trapped in this porous solid host For both systems, the ECL was found to be stable upon continuous oxidation or upon drying the gels in a high-humidity environment for over 10 days.
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31
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Loughnane BJ, Farrer RA, Scodinu A, Reilly T, Fourkas JT. Ultrafast Spectroscopic Studies of the Dynamics of Liquids Confined in Nanoporous Glasses. J Phys Chem B 2000. [DOI: 10.1021/jp000323h] [Citation(s) in RCA: 127] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Brian J. Loughnane
- Eugene F. Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467
| | - Richard A. Farrer
- Eugene F. Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467
| | - Alessandra Scodinu
- Eugene F. Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467
| | - Thomas Reilly
- Eugene F. Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467
| | - John T. Fourkas
- Eugene F. Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467
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Stolov AA, Morozov AI, Remizov AB. Infrared E-type band profiles of acetonitrile in condensed media: orientational diffusion and free rotation. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2000; 56:485-499. [PMID: 10794463 DOI: 10.1016/s1386-1425(99)00149-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Infrared spectra of liquid acetonitrile (CH3CN) and its solutions in CCl4, CS2, chloroform, dichloromethane, benzene-d6, acetone-d6 and dimethyl sulfoxide-d6 have been studied. E-type bands under investigation (v5 = 3009, v6 = 1448 and v7 = 1041 cm(-1)) were reproduced by the sum of two Cauchy-Gauss components, the narrower (n) and the broader (b) ones. The different temperature behaviour of the components has been found: the integrated intensities of the narrower components, In, decrease with the temperature, while the intensities of the broader ones, Ib, increase. The narrower components of the bands were explained within the framework of the orientational diffusion mechanism. The broader components of v6 and v7 were attributed to the unresolved gas-like vibration-rotational absorption of the molecules. The enthalpy difference between the molecules absorbing via these two different mechanisms was determined from the dependence of ln(In/Ib) upon T(-1) :deltaH0 = 1.26+/-0.15 kcal mol(-1). The broader component of v5 is assumed to be mainly due to interactions of C-H stretching vibrations with single particle and collective motions of molecular dipoles. The narrower components' widths were used for evaluating the spinning diffusion constant of CH3CN. The absorption in C-H stretching region was found to be strongly affected by solvent. These effects were explained within the framework of hydrogen bond formation between the CH3-group of acetonitrile and H-bond acceptor groups of the solvent molecules.
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Affiliation(s)
- A A Stolov
- Department of Chemistry, Kazan State University, Russia.
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Bryans TR, Wilde RE, Holtz MW, Quitevis EL. Autoregressive vibrational-dephasing analysis of the ν2 band of liquid methyl iodide in nanoporous glass. Chem Phys Lett 1999. [DOI: 10.1016/s0009-2614(99)01184-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Czeslik C, Kim YJ, Jonas J. Raman frequency noncoincidence effect of confined liquid dimethyl sulfoxide. J Chem Phys 1999. [DOI: 10.1063/1.480309] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Loughnane BJ, Farrer RA, Scodinu A, Fourkas JT. Dynamics of a wetting liquid in nanopores: An optical Kerr effect study of the dynamics of acetonitrile confined in sol-gel glasses. J Chem Phys 1999. [DOI: 10.1063/1.479768] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Morishige K, Kawano K. Freezing and Melting of Methyl Chloride in a Single Cylindrical Pore: Anomalous Pore-Size Dependence of Phase-Transition Temperature. J Phys Chem B 1999. [DOI: 10.1021/jp991177m] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kunimitsu Morishige
- Department of Chemistry, Okayama University of Science, 1-1 Ridai-cho, Okayama 700-0005, Japan
| | - Keizi Kawano
- Department of Chemistry, Okayama University of Science, 1-1 Ridai-cho, Okayama 700-0005, Japan
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Loughnane BJ, Fourkas JT. Geometric Effects in the Dynamics of a Nonwetting Liquid in Microconfinement: An Optical Kerr Effect Study of Methyl Iodide in Nanporous Glasses. J Phys Chem B 1998. [DOI: 10.1021/jp9830169] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Brian J. Loughnane
- Eugene F. Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467
| | - John T. Fourkas
- Eugene F. Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467
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Crupi V, Maisano G, Majolino D, Migliardo P, Venuti V. Dynamic evidence of chemical and physical traps in H-bonded confined liquids. J Chem Phys 1998. [DOI: 10.1063/1.477345] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Affiliation(s)
- Y. Shao
- Physics Department, TCU Box 298840, Fort Worth, Texas 76129
| | - T. W. Zerda
- Physics Department, TCU Box 298840, Fort Worth, Texas 76129
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Kirillov SA. Interactions and picosecond dynamics in molten salts: a rewiew with comparison to molecular liquids. J Mol Liq 1998. [DOI: 10.1016/s0167-7322(98)00052-x] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Carini G, Crupi V, D’Angelo G, Majolino D, Migliardo P, Mel’nichenko YB. Relaxation dynamics of H-bonded liquids confined in porous silica gels by Rayleigh wing spectroscopy. J Chem Phys 1997. [DOI: 10.1063/1.474605] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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The influence of the interaction of carbonyl compounds with the matrix walls on phosphorescence of their solution in porous glasses. Chem Phys 1997. [DOI: 10.1016/s0301-0104(97)00078-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Arndt M, Stannarius R, Gorbatschow W, Kremer F. Dielectric investigations of the dynamic glass transition in nanopores. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1996; 54:5377-5390. [PMID: 9965723 DOI: 10.1103/physreve.54.5377] [Citation(s) in RCA: 198] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Yi J, Jonas J. Raman Study of Vibrational and Rotational Relaxation of Liquid Benzene-d6 Confined to Nanoporous Silica Glasses. ACTA ACUST UNITED AC 1996. [DOI: 10.1021/jp9613955] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- J. Yi
- Department of Chemistry, School of Chemical Sciences and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801
| | - J. Jonas
- Department of Chemistry, School of Chemical Sciences and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801
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Affiliation(s)
- L. Sieminska
- Department of Pathophysiology, Slaska Akademia Medyczna, Traugutta 2, Zabrze, Poland
| | - T. W. Zerda
- Physics Department, Texas Christian University, P.O. Box 32915, Fort Worth, Texas 76129
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Mel’nichenko YB, Schüller J, Richert R, Ewen B, Loong C. Dynamics of hydrogen‐bonded liquids confined to mesopores: A dielectric and neutron spectroscopy study. J Chem Phys 1995. [DOI: 10.1063/1.469728] [Citation(s) in RCA: 148] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Bosong X, Kevan L. Photoionization of N,N,N′,N′-tetramethylbenzidine trapped in silica gel. Colloids Surf A Physicochem Eng Asp 1993. [DOI: 10.1016/0927-7757(93)80446-l] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Kirillov SA. Markovian frequency modulation in liquids. Analytical description and comparison with the stretched exponential approach. Chem Phys Lett 1993. [DOI: 10.1016/0009-2614(93)90030-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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