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Haro Mares NB, Döller SC, Wissel T, Hoffmann M, Vogel M, Buntkowsky G. Structures and Dynamics of Complex Guest Molecules in Confinement, Revealed by Solid-State NMR, Molecular Dynamics, and Calorimetry. Molecules 2024; 29:1669. [PMID: 38611950 PMCID: PMC11013127 DOI: 10.3390/molecules29071669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 03/29/2024] [Accepted: 04/05/2024] [Indexed: 04/14/2024] Open
Abstract
This review gives an overview of current trends in the investigation of confined molecules such as water, small and higher alcohols, carbonic acids, ethylene glycol, and non-ionic surfactants, such as polyethylene glycol or Triton-X, as guest molecules in neat and functionalized mesoporous silica materials employing solid-state NMR spectroscopy, supported by calorimetry and molecular dynamics simulations. The combination of steric interactions, hydrogen bonds, and hydrophobic and hydrophilic interactions results in a fascinating phase behavior in the confinement. Combining solid-state NMR and relaxometry, DNP hyperpolarization, molecular dynamics simulations, and general physicochemical techniques, it is possible to monitor these confined molecules and gain deep insights into this phase behavior and the underlying molecular arrangements. In many cases, the competition between hydrogen bonding and electrostatic interactions between polar and non-polar moieties of the guests and the host leads to the formation of ordered structures, despite the cramped surroundings inside the pores.
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Affiliation(s)
- Nadia B. Haro Mares
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Peter-Grünberg-Str. 8, D-64287 Darmstadt, Germany; (N.B.H.M.); (S.C.D.); (T.W.)
| | - Sonja C. Döller
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Peter-Grünberg-Str. 8, D-64287 Darmstadt, Germany; (N.B.H.M.); (S.C.D.); (T.W.)
| | - Till Wissel
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Peter-Grünberg-Str. 8, D-64287 Darmstadt, Germany; (N.B.H.M.); (S.C.D.); (T.W.)
| | - Markus Hoffmann
- Department of Chemistry and Biochemistry, State University of New York at Brockport, Brockport, NY 14420, USA
| | - Michael Vogel
- Institute for Condensed Matter Physics, Technische Universität Darmstadt, Hochschulstr. 6, D-64289 Darmstadt, Germany
| | - Gerd Buntkowsky
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Peter-Grünberg-Str. 8, D-64287 Darmstadt, Germany; (N.B.H.M.); (S.C.D.); (T.W.)
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2
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Harmon-Welch G, Hoefler JC, Trujillo MR, Bhuvanesh N, Bakhmutov VI, Blümel J. Creating Solid Solutions of Metallocenes: Migration of Nickelocene into the Ferrocene Crystal Lattice in the Absence of a Solvent. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2023; 127:3059-3066. [PMID: 38333002 PMCID: PMC10848251 DOI: 10.1021/acs.jpcc.2c07441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 01/20/2023] [Indexed: 02/10/2024]
Abstract
Ferrocene and nickelocene do not react with each other in solution; however, the large impact of the paramagnetic component on the ferrocene 1H NMR signal linewidth and relaxation times has been quantified. Co-crystallization of ferrocene and nickelocene at any ratio from a solvent can be explained with both pure substances crystallizing in the same space group P21/n. As a new phenomenon, when a ferrocene single crystal is exposed to polycrystalline nickelocene in the absence of a solvent, the nickelocene migrates into the ferrocene crystal lattice and a mixed crystal is formed that retains its macroscopic shape. This process has been proven visually by cutting the single crystal. Mixing polycrystalline ferrocene with polycrystalline nickelocene at different molar ratios with a mortar and pestle leads to crystalline solid solutions with the corresponding molar ratios of both components. This migration of one organometallic component into an existing crystal lattice of another at ambient temperature in the absence of a solvent has not been described previously. Paramagnetic 1H solid-state NMR spectroscopy of static and rotating samples of dry ferrocene/nickelocene mixtures at varying ratios is used to prove and quantify the mixing of both metallocenes at the molecular level. A single-crystal X-ray structure of a 50/50 mixed crystal corroborates the NMR results that nickelocene and ferrocene are randomly distributed in the lattice and that the space group P21/n is retained. All ferrocene molecules in the mixed crystal lattice show a broadening of their 1H wideline signals and residual magic-angle spinning (MAS) lines at ambient temperature. The broadening of the ferrocene signals correlates with the nickelocene content. 1H T1 relaxation time measurements for the signals of ferrocene in samples with different amounts of nickelocene corroborate the assumption that the signal broadening is due to paramagnetic dipole-dipole relaxation of ferrocene molecules in the vicinity of nickelocene. Spatially separated ferrocene and nickelocene powders in one rotor show the solid-state NMR characteristics of the individual polycrystalline metallocenes. The described formation of solid solutions of metallocenes in the absence of a solvent will open new pathways to homogeneously mixed nanoparticles with desired metal ratios and dual-atom catalysts.
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Affiliation(s)
| | - John C. Hoefler
- Department of Chemistry, Texas A&M University, College
Station, Texas 77845-3012, United States
| | - Martha R. Trujillo
- Department of Chemistry, Texas A&M University, College
Station, Texas 77845-3012, United States
| | - Nattamai Bhuvanesh
- Department of Chemistry, Texas A&M University, College
Station, Texas 77845-3012, United States
| | - Vladimir I. Bakhmutov
- Department of Chemistry, Texas A&M University, College
Station, Texas 77845-3012, United States
| | - Janet Blümel
- Department of Chemistry, Texas A&M University, College
Station, Texas 77845-3012, United States
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3
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Trzeciak K, Wielgus E, Kaźmierski S, Khalaji M, Dudek MK, Potrzebowski MJ. Unexpected Factors Affecting the Kinetics of Guest Molecule Release from Investigation of Binary Chemical Systems Trapped in a Single Void of Mesoporous Silica Particles. Chemphyschem 2022; 24:e202200884. [PMID: 36507917 DOI: 10.1002/cphc.202200884] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/09/2022] [Accepted: 12/09/2022] [Indexed: 12/15/2022]
Abstract
In this work, we present results for loading of well-defined binary systems (cocrystal, solid solution) and untreated materials (physical mixtures) into the voids of MCM-41 mesoporous silica particles employing three different filling methods. The applied techniques belong to the group of "wet methods" (diffusion supported loading - DiSupLo) and "solvent-free methods" (mechanical ball-mill loading - MeLo, thermal solvent free - TSF). As probes for testing the guest1-guest2 interactions inside the MCM-41 pores we employed the benzoic acid (BA), perfluorobenzoic acid (PFBA), and 4-fluorobenzoic acid (4-FBA). The guests intermolecular contacts and phase changes were monitored employing magic angle spinning (MAS) NMR Spectroscopy techniques and powder X-ray diffraction (PXRD). Since mesoporous silica materials are commonly used in drug delivery system research, special attention has been paid to factors affecting guest release kinetics. It has been proven that not only the content and composition of binary systems, but also the loading technique have a strong impact on the rate of guests release. Innovative methods of visualizing differences in release kinetics are presented.
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Affiliation(s)
- Katarzyna Trzeciak
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza Łódź, 112, 90-363, Lodz, Poland
| | - Ewelina Wielgus
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza Łódź, 112, 90-363, Lodz, Poland
| | - Sławomir Kaźmierski
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza Łódź, 112, 90-363, Lodz, Poland
| | - Mehrnaz Khalaji
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza Łódź, 112, 90-363, Lodz, Poland
| | - Marta K Dudek
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza Łódź, 112, 90-363, Lodz, Poland
| | - Marek J Potrzebowski
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza Łódź, 112, 90-363, Lodz, Poland
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4
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Benzie JW, Harmon-Welch GE, Hoefler JC, Bakhmutov VI, Blümel J. Molecular Dynamics and Surface Interactions of Nickelocene Adsorbed on Silica: A Paramagnetic Solid-State NMR Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:7422-7432. [PMID: 35675156 DOI: 10.1021/acs.langmuir.2c00301] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
When grinding nickelocene with silica in the absence of a solvent at room temperature, it adsorbs on the surface within the pores. This has also been demonstrated visually by adsorbing green nickelocene in the pores of a large colorless silica gel specimen. While this dry adsorption and translational mobility of nickelocene within the pores is proven visually, the site-to-site mobility of the nickelocene molecules and their orientation toward the surface are not yet understood. In this contribution, mesoporous silica is used as the support material for a systematic solid-state NMR study of these issues. Paramagnetic 1H VT solid-state NMR and T1 relaxation times have been powerful tools for studying the dynamics of nickelocene on the silica surface. Herewith, the mobility of the surface-adsorbed nickelocene molecules in the pores could be quantified on the molecular scale. According to the obtained data, the nickelocene molecules move like a liquid on the surface. Isotropically moving molecules exchange places rapidly with surface-attached molecular states of nickelocene in a sample with submonolayer surface coverage. This finding is corroborated by a macroscopic visualization experiment. The states of the surface-attached horizontally oriented nickelocene molecules that are prevalent at temperatures below 200 K have been quantified. The temperature dependencies of the rate k in coordinates of ln(k) versus 1/T and ln(k/T) versus 1/T form ideal straight lines that allow the determination of the kinetic parameters Eact = 5.5 kcal/mol, A = 1.1 × 1010, ΔH‡ = 5.0 kcal/mol, and ΔS‡ = -15 eu. Investigating a sample with equal amounts of nickelocene and ferrocene in a submonolayer amount of 80% overall surface coverage shows that the different metallocenes mix on the molecular level on the silica surface.
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Affiliation(s)
- Jordon W Benzie
- Department of Chemistry, Texas A&M University, College Station, Texas 77845-3012, United States
| | | | - John C Hoefler
- Department of Chemistry, Texas A&M University, College Station, Texas 77845-3012, United States
| | - Vladimir I Bakhmutov
- Department of Chemistry, Texas A&M University, College Station, Texas 77845-3012, United States
| | - Janet Blümel
- Department of Chemistry, Texas A&M University, College Station, Texas 77845-3012, United States
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5
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Lindner Ł, Bielejewski M, Markiewicz E, Łapiński A, Pankiewicz R, Tritt-Goc J. Synthesis and characterization of triazole based nanocrystalline cellulose solid proton conductors. Eur Polym J 2021. [DOI: 10.1016/j.eurpolymj.2021.110825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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6
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Buntkowsky G, Döller S, Haro-Mares N, Gutmann T, Hoffmann M. Solid-state NMR studies of non-ionic surfactants confined in mesoporous silica. Z PHYS CHEM 2021. [DOI: 10.1515/zpch-2021-3132] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Abstract
This review gives an overview of current trends in the investigation of confined molecules such as higher alcohols, ethylene glycol and polyethylene glycol as guest molecules in neat and functionalized mesoporous silica materials. All these molecules have both hydrophobic and hydrophilic parts. They are characteristic role-models for the investigation of confined surfactants. Their properties are studied by a combination of solid-state NMR and relaxometry with other physicochemical techniques and molecular dynamics techniques. It is shown that this combination delivers unique insights into the structure, arrangement, dynamical properties and the guest-host interactions inside the confinement.
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Affiliation(s)
- Gerd Buntkowsky
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie , Technische Universität Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
| | - Sonja Döller
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie , Technische Universität Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
| | - Nadia Haro-Mares
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie , Technische Universität Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
| | - Torsten Gutmann
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie , Technische Universität Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
| | - Markus Hoffmann
- Department of Chemistry and Biochemistry , State University of New York College at Brockport , Brockport , NY , 14420 , USA
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7
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Schoen M, Evans R, Gubbins KE, Rabe JP, Thommes M, Jackson G. Gerhard Findenegg (1938–2019). Mol Phys 2021. [DOI: 10.1080/00268976.2021.1953272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Martin Schoen
- Technische Universität Berlin, Fakultät für Mathematik und Naturwissenschaften, Berlin, Germany
| | - Robert Evans
- H. H. Wills Physics Laboratory, University of Bristol, Bristol, UK
| | - Keith E. Gubbins
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Jürgen P. Rabe
- Department of Physics & IRIS Adlershof, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Matthias Thommes
- Department of Chemical and Bioeengineering, Institute of Separation Science and Technology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - George Jackson
- Department of Chemical Engineering, Imperial College London, London, UK
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8
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Gonzalez-Nelson A, Mula S, Šimėnas M, Balčiu Nas S, Altenhof AR, Vojvodin CS, Canossa S, Banys JR, Schurko RW, Coudert FX, van der Veen MA. Emergence of Coupled Rotor Dynamics in Metal-Organic Frameworks via Tuned Steric Interactions. J Am Chem Soc 2021; 143:12053-12062. [PMID: 34324323 PMCID: PMC8361432 DOI: 10.1021/jacs.1c03630] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
The organic components
in metal–organic frameworks (MOFs)
are unique: they are embedded in a crystalline lattice, yet, as they
are separated from each other by tunable free space, a large variety
of dynamic behavior can emerge. These rotational dynamics of the organic
linkers are especially important due to their influence over properties
such as gas adsorption and kinetics of guest release. To fully exploit
linker rotation, such as in the form of molecular machines, it is
necessary to engineer correlated linker dynamics to achieve their
cooperative functional motion. Here, we show that for MIL-53, a topology
with closely spaced rotors, the phenylene functionalization allows
researchers to tune the rotors’ steric environment, shifting
linker rotation from completely static to rapid motions at frequencies
above 100 MHz. For steric interactions that start to inhibit independent
rotor motion, we identify for the first time the emergence of coupled
rotation modes in linker dynamics. These findings pave the way for
function-specific engineering of gear-like cooperative motion in MOFs.
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Affiliation(s)
- Adrian Gonzalez-Nelson
- Department of Chemical Engineering, Delft University of Technology, 2629 HZ Delft, The Netherlands.,DPI, P.O.Box 92, 5600 AX Eindhoven, The Netherlands
| | - Srinidhi Mula
- Department of Chemical Engineering, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | - Mantas Šimėnas
- Faculty of Physics, Vilnius University, LT-10222 Vilnius, Lithuania
| | | | - Adam R Altenhof
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, United States.,National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
| | - Cameron S Vojvodin
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, United States.,National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
| | - Stefano Canossa
- EMAT, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
| | - Ju Ras Banys
- Faculty of Physics, Vilnius University, LT-10222 Vilnius, Lithuania
| | - Robert W Schurko
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, United States.,National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
| | - François-Xavier Coudert
- Chimie ParisTech, PSL University, CNRS, Institut de Recherche de Chimie Paris, 75005 Paris, France
| | - Monique A van der Veen
- Department of Chemical Engineering, Delft University of Technology, 2629 HZ Delft, The Netherlands
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9
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Trzeciak K, Chotera-Ouda A, Bak-Sypien II, Potrzebowski MJ. Mesoporous Silica Particles as Drug Delivery Systems-The State of the Art in Loading Methods and the Recent Progress in Analytical Techniques for Monitoring These Processes. Pharmaceutics 2021; 13:pharmaceutics13070950. [PMID: 34202794 PMCID: PMC8309060 DOI: 10.3390/pharmaceutics13070950] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 06/17/2021] [Accepted: 06/21/2021] [Indexed: 12/17/2022] Open
Abstract
Conventional administration of drugs is limited by poor water solubility, low permeability, and mediocre targeting. Safe and effective delivery of drugs and therapeutic agents remains a challenge, especially for complex therapies, such as cancer treatment, pain management, heart failure medication, among several others. Thus, delivery systems designed to improve the pharmacokinetics of loaded molecules, and allowing controlled release and target specific delivery, have received considerable attention in recent years. The last two decades have seen a growing interest among scientists and the pharmaceutical industry in mesoporous silica nanoparticles (MSNs) as drug delivery systems (DDS). This interest is due to the unique physicochemical properties, including high loading capacity, excellent biocompatibility, and easy functionalization. In this review, we discuss the current state of the art related to the preparation of drug-loaded MSNs and their analysis, focusing on the newest advancements, and highlighting the advantages and disadvantages of different methods. Finally, we provide a concise outlook for the remaining challenges in the field.
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10
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Buntkowsky G, Vogel M. Small Molecules, Non-Covalent Interactions, and Confinement. Molecules 2020; 25:E3311. [PMID: 32708283 PMCID: PMC7397022 DOI: 10.3390/molecules25143311] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 07/07/2020] [Accepted: 07/15/2020] [Indexed: 11/27/2022] Open
Abstract
This review gives an overview of current trends in the investigation of small guest molecules, confined in neat and functionalized mesoporous silica materials by a combination of solid-state NMR and relaxometry with other physico-chemical techniques. The reported guest molecules are water, small alcohols, and carbonic acids, small aromatic and heteroaromatic molecules, ionic liquids, and surfactants. They are taken as characteristic role-models, which are representatives for the typical classes of organic molecules. It is shown that this combination delivers unique insights into the structure, arrangement, dynamics, guest-host interactions, and the binding sites in these confined systems, and is probably the most powerful analytical technique to probe these systems.
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Affiliation(s)
- Gerd Buntkowsky
- Institut für Physikalische Chemie, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Michael Vogel
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64295 Darmstadt, Germany
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11
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Wang J, Zhang X, Graf R, Li Y, Yang G, Fu XB, Ma JQ, Yao YF. A Small Lattice Change Induces Significant Dynamic Changes of CH 3NH 3+ Caged in Hybrid Perovskite Crystals: Toward Understanding the Interplay between Host Lattices and Guest Molecules. Inorg Chem 2019; 58:7426-7432. [PMID: 31091094 DOI: 10.1021/acs.inorgchem.9b00497] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Two perovskite-type compounds, (MA)2[B'Co(CN)6] (MA = methylammonium, B' = K(I) and Na(I)), have very similar structures, but exhibit marked differences in the phase and dielectric transitions. Solid state 2H NMR studies reveal the detailed dynamic changes of the caged methylammonium (MA) cations before and after the phase transitions, which are correlated with the different dielectric states of the compounds. Using solid state 59Co NMR, the dynamic changes of the host lattices before and after the transitions, which accompany the changes in the dynamics of the caged MA cations, are unveiled, demonstrating the intriguing interplay between the MA cations and the host lattices. On the basis of these observations, the molecular origins of the dielectric transitions are discussed in detail.
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Affiliation(s)
- Jiachen Wang
- Physics Department & Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science , East China Normal University , North Zhongshan Road 3663 , Shanghai 200062 , P. R. China
| | - Xi Zhang
- Physics Department & Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science , East China Normal University , North Zhongshan Road 3663 , Shanghai 200062 , P. R. China
| | - Robert Graf
- Max-Planck-Institute for Polymer Research , Ackermannweg 10 , 55128 Mainz , Germany
| | - Yi Li
- Physics Department & Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science , East China Normal University , North Zhongshan Road 3663 , Shanghai 200062 , P. R. China
| | - Guang Yang
- Physics Department & Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science , East China Normal University , North Zhongshan Road 3663 , Shanghai 200062 , P. R. China
| | - Xiao-Bin Fu
- Physics Department & Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science , East China Normal University , North Zhongshan Road 3663 , Shanghai 200062 , P. R. China
| | - Jia-Qi Ma
- Physics Department & Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science , East China Normal University , North Zhongshan Road 3663 , Shanghai 200062 , P. R. China
| | - Ye-Feng Yao
- Physics Department & Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science , East China Normal University , North Zhongshan Road 3663 , Shanghai 200062 , P. R. China
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12
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Bakhmutov VI, Elliott DW, Contreras AR, Clearfield A. Guest Molecules in a Layered Microporous Tin(IV) Phosphonate-Phosphate Material: Solid State NMR Studies. J Phys Chem A 2018; 122:9901-9909. [PMID: 30500193 DOI: 10.1021/acs.jpca.8b09144] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
There is little systematic understanding of pore surfaces in layered microporous metal(IV) phosphate-phosphonate materials and their interactions with guest molecules. In this paper, we show how to probe the mobility of guest molecules in such poorly crystalline systems using multinuclear solid-state NMR and relaxation time measurements. Anisotropic motions of benzene- d6 molecules absorbed on the pore walls of material Sn(O3PC6H4PO3)0.85(O3POH)0.33 (1) have been recognized as the fast in-plane C6 rotation due to metal-π interactions with pore walls. The benzene- d6 absorption enthalpy due to Sn···π interactions has been determined as -Δ H = 5.9 kcal/mol. Specific interactions between pyridine and the pore walls of 1 have been observed as immobile pyridine, the population of which grows strongly at low temperatures to show thermodynamic parameters -Δ H of 5.0 kcal/mol and Δ S of -11.0 e.u. It has been suggested that these parameters characterize N···H-OP hydrogen bonding as a driving force for accumulation of immobile pyridine molecules in pores of compound 1.
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Affiliation(s)
- Vladimir I Bakhmutov
- Department of Chemistry , Texas A&M University , P.O. Box 30012, College Station , Texas 77842-3012 , United States
| | - Douglas W Elliott
- Department of Chemistry , Texas A&M University , P.O. Box 30012, College Station , Texas 77842-3012 , United States
| | - Aida R Contreras
- Department of Chemistry , Texas A&M University , P.O. Box 30012, College Station , Texas 77842-3012 , United States
| | - Abraham Clearfield
- Department of Chemistry , Texas A&M University , P.O. Box 30012, College Station , Texas 77842-3012 , United States
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13
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Contreras AR, Bakhmutov VI, Elliott DW, Clearfield A. Benzene-d 6 and toluene-d 8 as guest molecules in micropores of a layered zirconium phosphonate: 2 H, 13 C{ 1 H}, and 31 P{ 1 H} solid-state NMR, deuterium NMR relaxation, and molecular motions. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2018; 56:1158-1167. [PMID: 29974552 DOI: 10.1002/mrc.4779] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 06/04/2018] [Accepted: 06/26/2018] [Indexed: 06/08/2023]
Abstract
For the first time, pore spaces in the Zr (IV) phosphonate (1) as a representative of layered metal (IV) phosphonate materials have been investigated by studying mobility of guest molecules, benzene-d6 , and toluene-d8 . Guest molecules located in micropores of 1 have been characterized by solid-state 13 C{1 H} and 2 H NMR spectra in static samples with varying temperatures. At moderately low temperatures, the benzene and toluene molecules experience fast isotropic reorientations and show the motionally averaged liquid-like carbon and deuterium line shapes in the NMR spectra. At lower temperatures, two anisotropic motional modes have been found for benzene molecules by analyzing the 2 H NMR line shapes: the well-known in-plane C6 rotation and composite motions. Interpretation of the variable-temperature 2 H T1 relaxation times identifies the composite motions as 120° flips around the C6 axis perpendicular to the molecular plane and the rotations around the molecular para-C-C axis. The data obtained resulted in the idealized (cylinder-shaped) model of micropores in compound 1 with the diameter of 20-30 Å. Furthermore, the activation energy of 20.1 kJ/mol determined for the benzene motions classifies the molecule-surface interactions as weak but enough for absorption.
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Affiliation(s)
- Aida R Contreras
- Department of Chemistry, Texas A&M University, College Station, Texas, USA
| | | | - Douglas W Elliott
- Department of Chemistry, Texas A&M University, College Station, Texas, USA
| | - Abraham Clearfield
- Department of Chemistry, Texas A&M University, College Station, Texas, USA
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14
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Abstract
Abstract
Effects of interfaces on hydrogen-bonded liquids play major roles in nature and technology. Despite their importance, a fundamental understanding of these effects is still lacking. In large parts, this shortcoming is due to the high complexity of these systems, leading to an interference of various interactions and effects. Therefore, it is advisable to take gradual approaches, which start from well designed and defined model systems and systematically increase the level of intricacy towards more complex mimetics. Moreover, it is necessary to combine insights from a multitude of methods, in particular, to link novel preparation strategies and comprehensive experimental characterization with inventive computational and theoretical modeling. Such concerted approach was taken by a group of preparative, experimentally, and theoretically working scientists in the framework of Research Unit FOR 1583 funded by the Deutsche Forschungsgemeinschaft (German Research Foundation). This special issue summarizes the outcome of this collaborative research. In this introductory article, we give an overview of the covered topics and the main results of the whole consortium. The following contributions are review articles or original works of individual research projects.
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Affiliation(s)
- Gerd Buntkowsky
- Institut für Physikalische Chemie , Technische Universität Darmstadt , 64287 Darmstadt , Germany
| | - Michael Vogel
- Institut für Festkörperphysik , Technische Universität Darmstadt , 64295 Darmstadt , Germany
| | - Roland Winter
- Fakultät für Chemie und Chemische Biologie , Technische Universität Dortmund , 44227 Dortmund , Germany
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15
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Shi C, Zhang X, Yu CH, Yao YF, Zhang W. Geometric isotope effect of deuteration in a hydrogen-bonded host-guest crystal. Nat Commun 2018; 9:481. [PMID: 29396512 PMCID: PMC5797174 DOI: 10.1038/s41467-018-02931-8] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 01/09/2018] [Indexed: 11/11/2022] Open
Abstract
Deuteration of a hydrogen bond by replacing protium (H) with deuterium (D) can cause geometric changes in the hydrogen bond, known as the geometric H/D isotope effect (GIE). Understanding the GIEs on global structures and bulk properties is of great importance to study structure–property relationships of hydrogen-bonded systems. Here, we report a hydrogen-bonded host–guest crystal, imidazolium hydrogen terephthalate, that exemplifies striking GIEs on its hydrogen bonds, phases, and bulk dielectric transition property. Upon deuteration, the donor–acceptor distance in the O–H···O hydrogen bonds in the host structure is found to increase, which results in a change in the global hydrogen-bonded supramolecular structure and the emergence of a new phase (i.e., isotopic polymorphism). Consequently, the dynamics of the confined guest, which depend on the internal pressure exerted by the host framework, are substantially altered, showing a downward shift of the dielectric switching temperature. Deuterating a hydrogen bond can change the bond’s geometry, a phenomenon known as the geometric isotope effect (GIE). Here, the authors find that a hydrogen-bonded host–guest crystal, imidazolium hydrogen terephthalate, exhibits significant GIE on its hydrogen bonds, changing its crystal phases and bulk dielectric properties.
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Affiliation(s)
- Chao Shi
- Ordered Matter Science Research Center and Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics, Southeast University, 211189, Nanjing, China
| | - Xi Zhang
- Department of Physics & Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science, East China Normal University, North Zhongshan Road 3663, 200062, Shanghai, China
| | - Chun-Hua Yu
- Ordered Matter Science Research Center and Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics, Southeast University, 211189, Nanjing, China
| | - Ye-Feng Yao
- Department of Physics & Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science, East China Normal University, North Zhongshan Road 3663, 200062, Shanghai, China. .,NYU-ECNU Institute of Physics at NYU Shanghai, 3663 Zhongshan Road North, 200062, Shanghai, China.
| | - Wen Zhang
- Ordered Matter Science Research Center and Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics, Southeast University, 211189, Nanjing, China.
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16
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Catalano J, Murphy A, Yao Y, Zumbulyadis N, Centeno SA, Dybowski C. Molecular dynamics of palmitic acid and lead palmitate in cross-linked linseed oil films: Implications from deuterium magnetic resonance for lead soap formation in traditional oil paintings. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2018; 89:21-26. [PMID: 29277314 DOI: 10.1016/j.ssnmr.2017.12.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 12/04/2017] [Accepted: 12/06/2017] [Indexed: 06/07/2023]
Abstract
Many oil paintings, dating from the 15th century to the present, are affected by the formation of heavy-metal carboxylates (soaps) that alter the structural integrity and appearance of the works. Through transport phenomena not yet understood, free fatty acids formed from oils used as binders migrate through the paint film and react with heavy-metal ions that are constituents of pigments and/or driers, forming metal carboxylates. The local molecular dynamics of fatty acids and metal carboxylates are factors influencing material transport in these systems. We report temperature-dependent 2H NMR spectra of palmitic acid and lead palmitate as pure materials, in cross-linked linseed oil films, and in a lead white linseed oil paint film as part of our broader research into metal soap formation. Local dynamics at the α carbon, at the terminal methyl group, and at the middle of the fatty acid chain were observed in specifically deuterated materials. Changes in the dynamic behavior with temperature were observed by the appearance of two species, a solid-like material and a liquid-like material. The relative amounts of the two phases and their deuterium NMR parameters indicate that the amount of liquid-like material and the local dynamics at that site increase with temperature. At the three locations along the chain and at all temperatures, there is a larger percentage of acyl chains of both palmitic acid and lead palmitate that are "mobile" or liquid-like in linseed oil films than there are in the pure materials. However, the percentage of liquid-like species is decreased in a lead white paint film, as compared to a linseed oil matrix. In addition, these experiments indicate that there is a larger percentage of liquid-like acyl chains of palmitic acid than of lead palmitate under identical conditions in these model paint systems.
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Affiliation(s)
- Jaclyn Catalano
- Department of Chemistry and Biochemistry, Montclair State University, Montclair, NJ, USA
| | - Anna Murphy
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA
| | - Yao Yao
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA
| | | | - Silvia A Centeno
- Department of Scientific Research, The Metropolitan Museum of Art, New York, NY, USA
| | - Cecil Dybowski
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA.
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17
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Brodrecht M, Kumari B, Breitzke H, Gutmann T, Buntkowsky G. Chemically Modified Silica Materials as Model Systems for the Characterization of Water-Surface Interactions. ACTA ACUST UNITED AC 2018. [DOI: 10.1515/zpch-2017-1059] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Abstract
A series of novel functionalized mesoporous silica-based materials with well-defined pore diameters, surface functionalization and surface morphology is synthesized by co-condensation or grafting techniques and characterized by solid-state NMR spectroscopy, DNP enhanced solid state-NMR and thermodynamic techniques. These materials are employed as host-systems for small-guest molecules like water, small alcohols, carbonic acids, small aromatic molecules, binary mixtures and others. The phase-behavior of these confined guests is studied by combinations of one dimensional solid-state NMR techniques (1H MAS, 2H-line shape analysis, 13C CPMAS) and two-dimensional correlation experiments like 1H-29Si- solid-state HETCOR.
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Affiliation(s)
- Martin Brodrecht
- Eduard-Zintl-Institute of Inorganic and Physical Chemistry, Technical University of Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
| | - Bharti Kumari
- Eduard-Zintl-Institute of Inorganic and Physical Chemistry, Technical University of Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
| | - Hergen Breitzke
- Eduard-Zintl-Institute of Inorganic and Physical Chemistry, Technical University of Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
| | - Torsten Gutmann
- Eduard-Zintl-Institute of Inorganic and Physical Chemistry, Technical University of Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
| | - Gerd Buntkowsky
- Eduard-Zintl-Institute of Inorganic and Physical Chemistry, Technical University of Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
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18
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Veena VS, Illath K, Lazar A, Vinod CP, Ajithkumar TG, Jayanthi S. Distribution of water in the pores of periodic mesoporous organosilicates – a proton solid state MAS NMR study. Phys Chem Chem Phys 2018; 20:29351-29361. [DOI: 10.1039/c8cp04902e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Proposed model of water layers and pore filling in ethane substituted periodic mesoporous organosilicates (PMOE) based on analysis of solid state magic angle spinning (MAS) proton NMR spectra.
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Affiliation(s)
- V. S. Veena
- Department of Physics
- Indian Institute of Space Science and Technology
- Thiruvananthapuram 695 547
- India
| | - Kavya Illath
- Central NMR Facility and Physical and Materials Chemistry Division
- CSIR-National Chemical Laboratory
- Pune
- India
| | - Anish Lazar
- Catalysis and Inorganic Chemistry Division
- CSIR-National Chemical Laboratory
- Pune
- India
| | - C. P. Vinod
- Catalysis and Inorganic Chemistry Division
- CSIR-National Chemical Laboratory
- Pune
- India
| | - T. G. Ajithkumar
- Central NMR Facility and Physical and Materials Chemistry Division
- CSIR-National Chemical Laboratory
- Pune
- India
| | - S. Jayanthi
- Department of Physics
- Indian Institute of Space Science and Technology
- Thiruvananthapuram 695 547
- India
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19
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Brodrecht M, Klotz E, Lederle C, Breitzke H, Stühn B, Vogel M, Buntkowsky G. A Combined Solid-State NMR, Dielectric Spectroscopy and Calorimetric Study of Water in Lowly Hydrated MCM-41 Samples. Z PHYS CHEM 2017. [DOI: 10.1515/zpch-2017-1030] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The processes of drying mesoporous silica materials and their refilling with water have been examined by magic-angle spinning (MAS) solid-state NMR, broadband dielectric spectroscopy (BDS), and differential scanning calorimetry (DSC). It is shown that different drying protocols strongly influence the amount and types of hydroxy-species inside the pores. It is found that a very good vacuum (≈10−6 bar) is necessary to remove all H2O molecules from the silica matrices in order to accurately refill them with very low amounts of water such as e.g. a mono- or submonolayer coverage of the surface. Time-dependent 1H-NMR-spectra recorded after loading the samples indicate a very specific course of water first existing in a bulk-like form inside the pores and then distributing itself through the pores by hydrogen bonding to surface silanol groups. After assuring accurate sample loading, we were able to investigate lowly hydrated samples of water confined in MCM-41 via DCS and BDS at temperatures below the freezing point of free bulk-water (0°C) and find two non-crystallizing water species with Arrhenius behavior and activation energies of 0.53 eV (51.1 kJ/mol).
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Affiliation(s)
- Martin Brodrecht
- Institut für Physikalische Chemie , Technische Universität Darmstadt , 64287 Darmstadt , Germany
| | - Edda Klotz
- Institut für Festkörperphysik , Technische Universität Darmstadt , 64289 Darmstadt , Germany
| | - Christina Lederle
- Institut für Festkörperphysik , Technische Universität Darmstadt , 64289 Darmstadt , Germany
| | - Hergen Breitzke
- Institut für Physikalische Chemie , Technische Universität Darmstadt , 64287 Darmstadt , Germany
| | - Bernd Stühn
- Institut für Festkörperphysik , Technische Universität Darmstadt , 64289 Darmstadt , Germany
| | - Michael Vogel
- Institut für Festkörperphysik , Technische Universität Darmstadt , 64289 Darmstadt , Germany
| | - Gerd Buntkowsky
- Institut für Physikalische Chemie , Technische Universität Darmstadt , 64287 Darmstadt , Germany
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20
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Chen C, Wong K, Mole RA, Yu D, Chathoth SM. The logarithmic relaxation process and the critical temperature of liquids in nano-confined states. Sci Rep 2016; 6:33374. [PMID: 27671486 PMCID: PMC5037365 DOI: 10.1038/srep33374] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 08/25/2016] [Indexed: 01/21/2023] Open
Abstract
The logarithmic relaxation process is the slowest of all relaxation processes and is exhibited by only a few molecular liquids and proteins. Bulk salol, which is a glass-forming liquid, is known to exhibit logarithmic decay of intermediate scattering function for the β-relaxation process. In this article, we report the influence of nanoscale confinements on the logarithmic relaxation process and changes in the microscopic glass-transition temperature of salol in the carbon and silica nanopores. The generalized vibrational density-of-states of the confined salol indicates that the interaction of salol with ordered nanoporous carbon is hydrophilic in nature whereas the interaction with silica surfaces is more hydrophobic. The mode-coupling theory critical temperature derived from the QENS data shows that the dynamic transition occurs at much lower temperature in the carbon pores than in silica pores. The results of this study indicate that, under nano-confinements, liquids that display logarithmic β-relaxation phenomenon undergo a unique glass transition process.
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Affiliation(s)
- Changjiu Chen
- Department of Physics and Materials Science, City University of Hong Kong, Hong Kong, 999077, P. R. China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen, 518057, P. R. China
| | - Kaikin Wong
- Department of Physics and Materials Science, City University of Hong Kong, Hong Kong, 999077, P. R. China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen, 518057, P. R. China
| | - Richard A Mole
- Australian Nuclear Science and Technology Organization, Lucas Heights, NSW 2234, Australia
| | - Dehong Yu
- Australian Nuclear Science and Technology Organization, Lucas Heights, NSW 2234, Australia
| | - Suresh M Chathoth
- Department of Physics and Materials Science, City University of Hong Kong, Hong Kong, 999077, P. R. China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen, 518057, P. R. China
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21
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Bendeif EE, Gansmuller A, Hsieh KY, Pillet S, Woike T, Zobel M, Neder RB, Bouazaoui M, El Hamzaoui H, Schaniel D. Structure determination of molecular nanocomposites by combining pair distribution function analysis and solid-state NMR. RSC Adv 2015. [DOI: 10.1039/c4ra11470a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Total X-ray scattering coupled to atomic pair distribution function analysis (PDF) and solid state NMR allowed the identification and structural characterisation of isolated molecules and nanocrystals of sodium nitroprusside confined in mesoporous silica.
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22
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Szymocha AM, Lalowicz ZT, Birczyński A, Krzystyniak M, Stoch G, Góra-Marek K. Water Confinement in Faujasite Cages: A Deuteron NMR Investigation in a Wide Temperature Range. 2. Spectra and Relaxation at High Temperature. J Phys Chem A 2014; 118:5371-80. [DOI: 10.1021/jp502827x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Z. T. Lalowicz
- H. Niewodniczański Institute of Nuclear Physics PAS, ul. Radzikowskiego 152, 31-342 Kraków, Poland
| | - A. Birczyński
- H. Niewodniczański Institute of Nuclear Physics PAS, ul. Radzikowskiego 152, 31-342 Kraków, Poland
| | - M. Krzystyniak
- ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11
0QX, U.K
- School
of Science and Technology, The Nottingham Trent University, Clifton
Lane, Nottingham NG11 8NS, U.K
| | - G. Stoch
- H. Niewodniczański Institute of Nuclear Physics PAS, ul. Radzikowskiego 152, 31-342 Kraków, Poland
| | - K. Góra-Marek
- Faculty
of Chemistry, Jagellonian University, 30-060 Kraków, Poland
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23
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Sattig M, Reutter S, Fujara F, Werner M, Buntkowsky G, Vogel M. NMR studies on the temperature-dependent dynamics of confined water. Phys Chem Chem Phys 2014; 16:19229-40. [DOI: 10.1039/c4cp02057j] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
NMR studies of water in nanoscopic confinements of various sizes reveal two dynamical crossovers related to a partial solidification of internal molecules and a glass transition of interfacial molecules, respectively.
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Affiliation(s)
- Matthias Sattig
- Institut für Festkörperphysik
- Technische Universität Darmstadt
- 64289 Darmstadt, Germany
| | - Stefan Reutter
- Institut für Festkörperphysik
- Technische Universität Darmstadt
- 64289 Darmstadt, Germany
| | - Franz Fujara
- Institut für Festkörperphysik
- Technische Universität Darmstadt
- 64289 Darmstadt, Germany
| | - Mayke Werner
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie
- Technische Universität Darmstadt
- 64287 Darmstadt, Germany
| | - Gerd Buntkowsky
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie
- Technische Universität Darmstadt
- 64287 Darmstadt, Germany
| | - Michael Vogel
- Institut für Festkörperphysik
- Technische Universität Darmstadt
- 64289 Darmstadt, Germany
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24
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Xu Y, Watermann T, Limbach HH, Gutmann T, Sebastiani D, Buntkowsky G. Water and small organic molecules as probes for geometric confinement in well-ordered mesoporous carbon materials. Phys Chem Chem Phys 2014; 16:9327-36. [DOI: 10.1039/c4cp00808a] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Confinement effects on water, benzene and pyridine in mesoporous carbon materials were probed by 1H-MAS NMR and chemical shift calculations.
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Affiliation(s)
- Yeping Xu
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie
- Technische Universität Darmstadt
- D-64287 Darmstadt, Germany
| | - Tobias Watermann
- Institut für Chemie
- Martin-Luther-Universität Halle-Wittenberg
- 06120 Halle, Germany
| | - Hans-Heinrich Limbach
- Institut für Physikalische und Theoretische Chemie
- Freie Universität Berlin
- D-14195 Berlin, Germany
| | - Torsten Gutmann
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie
- Technische Universität Darmstadt
- D-64287 Darmstadt, Germany
| | - Daniel Sebastiani
- Institut für Chemie
- Martin-Luther-Universität Halle-Wittenberg
- 06120 Halle, Germany
| | - Gerd Buntkowsky
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie
- Technische Universität Darmstadt
- D-64287 Darmstadt, Germany
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25
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Chiba R, Kuroiwa Y, Higashi K, Yamamoto K, Moribe K. Characterization of as-synthesized mesoporous silica using NMR and solid-state fluorescence spectroscopy. J Drug Deliv Sci Technol 2014. [DOI: 10.1016/s1773-2247(14)50135-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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26
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Rimola A, Costa D, Sodupe M, Lambert JF, Ugliengo P. Silica surface features and their role in the adsorption of biomolecules: computational modeling and experiments. Chem Rev 2013; 113:4216-313. [PMID: 23289428 DOI: 10.1021/cr3003054] [Citation(s) in RCA: 328] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Albert Rimola
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallès), Spain
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27
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Melting of Low Molecular Weight Compounds in Confinement Observed by 2H-Solid State NMR: Biphenyl, a Case Study. ACTA ACUST UNITED AC 2012. [DOI: 10.1524/zpch.2012.0304] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
The 2H-NMR solid echo spectra of biphenyl molecules as guests in the mesopores of neat and silylated SBA-15 have been measured as a function of temperature. At low temperatures typical 2H-Pake patterns with parameters of (Q
zz
=132 kHz, corresponding to Q
cc
=176 kHz) and (η=0.04) are observed. All samples exhibit a strong reduction of the melting point from the bulk value of 342.4 K to values between 222 K and 229 K, depending on both the pore diameter and the surface state and a glass like behavior of the biphenyl molecules in the melting regime. Employing the Roessler two-phase model of the modeling of glass-transitions by 2H-solid state NMR the distribution of activation energies for the rotational motions has been determined. At temperatures closely below the glass-transition temperature deviations from a static Pake pattern of an aromatic deuteron are observed, which indicate a pre-melting motion of biphenyl, which could be caused by C2-ring flips of the phenyl rings.
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28
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Jayanthi S, Frydman V, Vega S. Dynamic Deuterium Magic Angle Spinning NMR of a Molecule Grafted at the Inner Surface of a Mesoporous Material. J Phys Chem B 2012; 116:10398-405. [DOI: 10.1021/jp3061152] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- S. Jayanthi
- Department of Chemical
Physics, Weizmann Institute of Science, Rechovot, Israel 76100
| | - V. Frydman
- Department of Chemical
Physics, Weizmann Institute of Science, Rechovot, Israel 76100
| | - S. Vega
- Department of Chemical
Physics, Weizmann Institute of Science, Rechovot, Israel 76100
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29
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Haumann M, Schönweiz A, Breitzke H, Buntkowsky G, Werner S, Szesni N. Solid-State NMR Investigations of Supported Ionic Liquid Phase Water-Gas Shift Catalysts: Ionic Liquid Film Distribution vs. Catalyst Performance. Chem Eng Technol 2012. [DOI: 10.1002/ceat.201200025] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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30
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Lee HS, Kim WH, Lee JH, Choi DJ, Jeong YK, Chang JH. Transition metal-chelating surfactant micelle templates for facile synthesis of mesoporous silica nanoparticles. J SOLID STATE CHEM 2012. [DOI: 10.1016/j.jssc.2011.10.037] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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31
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Hudson ZM, Sun C, Harris KJ, Lucier BEG, Schurko RW, Wang S. Probing the Structural Origins of Vapochromism of a Triarylboron-Functionalized Platinum(II) Acetylide by Optical and Multinuclear Solid-State NMR Spectroscopy. Inorg Chem 2011; 50:3447-57. [DOI: 10.1021/ic102349h] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zachary M. Hudson
- Department of Chemistry, Queen’s University, 90 Bader Lane, Kingston, Ontario, Canada K7L 3N6
| | - Christina Sun
- Department of Chemistry, Queen’s University, 90 Bader Lane, Kingston, Ontario, Canada K7L 3N6
| | - Kristopher J. Harris
- Department of Chemistry & Biochemistry, University of Windsor, 401 Sunset Avenue, Windsor, Ontario, Canada N9B 3P4
| | - Bryan E. G. Lucier
- Department of Chemistry & Biochemistry, University of Windsor, 401 Sunset Avenue, Windsor, Ontario, Canada N9B 3P4
| | - Robert W. Schurko
- Department of Chemistry & Biochemistry, University of Windsor, 401 Sunset Avenue, Windsor, Ontario, Canada N9B 3P4
| | - Suning Wang
- Department of Chemistry, Queen’s University, 90 Bader Lane, Kingston, Ontario, Canada K7L 3N6
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32
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Blochowicz T, Lusceac SA, Gutfreund P, Schramm S, Stühn B. Two Glass Transitions and Secondary Relaxations of Methyltetrahydrofuran in a Binary Mixture. J Phys Chem B 2011; 115:1623-37. [DOI: 10.1021/jp110506z] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- T. Blochowicz
- Institut für Festkörperphysik, TU-Darmstadt, 64289 Darmstadt, Germany
| | - S. A. Lusceac
- Institut für Festkörperphysik, TU-Darmstadt, 64289 Darmstadt, Germany
| | - P. Gutfreund
- Institut Laue-Langevin, 38042 Grenoble Cedex, France
| | - S. Schramm
- Institut für Festkörperphysik, TU-Darmstadt, 64289 Darmstadt, Germany
| | - B. Stühn
- Institut für Festkörperphysik, TU-Darmstadt, 64289 Darmstadt, Germany
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33
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Ueda T, Omichi H, Chen Y, Kobayashi H, Kubota O, Miyakubo K, Eguchi T. 2H NMR study of 2D melting and dynamic behaviour of CDCl3 confined in ACF nanospace. Phys Chem Chem Phys 2010; 12:9222-9. [PMID: 20582342 DOI: 10.1039/b922681h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two-dimensional melting of trichloromethane (chloroform) confined in activated carbon fibre was investigated using differential thermal analysis and (2)H NMR techniques. Differential thermal analysis revealed a thermal anomaly with an endothermic peak at 269 K, which was distributed from 250 K to 287 K on the heating direction. This anomaly was also observed upon cooling at the same temperature. Furthermore, (2)H NMR revealed that slow motion such as molecular hopping and/or diffusion of CDCl(3) in ACF affected the spectral line width. The temperature dependence (Arrhenius plot) of the spectral line width showed an inflection point at 227 K. The activation energy of molecular motion of CDCl(3) in ACF was 4 kJ mol(-1) at temperatures greater than 227 K and 7.7 kJ mol(-1) at temperatures less than 227 K. Reduction of the activation energy suggests that the average intermolecular distance between CDCl(3) molecules enlarges above the inflection point. The difference of activation energy (3.7 kJ mol(-1)) is close to the enthalpy of fusion in typical plastic crystals. These results reveal that the thermal anomaly and the transition of dynamic process correspond respectively to melting of CHCl(3) in ACF and the pre-melting phenomenon.
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Affiliation(s)
- Takahiro Ueda
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
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Ben Shir I, Kababya S, Amitay-Rosen T, Balazs YS, Schmidt A. Molecular level characterization of the inorganic-bioorganic interface by solid state NMR: alanine on a silica surface, a case study. J Phys Chem B 2010; 114:5989-96. [PMID: 20397675 DOI: 10.1021/jp100114v] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The molecular interface between bioorganics and inorganics plays a key role in diverse scientific and technological research areas including nanoelectronics, biomimetics, biomineralization, and medical applications such as drug delivery systems and implant coatings. However, the physical/chemical basis of recognition of inorganic surfaces by biomolecules remains unclear. The molecular level elucidation of specific interfacial interactions and the structural and dynamical state of the surface bound molecules is of prime scientific importance. In this study, we demonstrate the ability of solid state NMR methods to accomplish these goals. L-[1-(13)C,(15)N]Alanine loaded onto SBA-15 mesoporous silica with a high surface area served as a model system. The interacting alanine moiety was identified as the -NH(3)(+) functional group by (15)N{(1)H}SLF NMR. (29)Si{(15)N} and (15)N{(29)Si}REDOR NMR revealed intermolecular interactions between the alanine -NH(3)(+) and three to four surface Si species, predominantly Q(3), with similar internuclear N...Si distances of 4.0-4.2 A. Distinct dynamic states of the adsorbed biomolecules were identified by (15)N{(13)C}REDOR NMR, indicating both bound and free alanine populations, depending on hydration level and temperature. In the bound populations, the -NH(3)(+) group is surface anchored while the free carboxylate end undergoes librations, implying the carboxylate has small or no contributions to surface binding. When surface water clusters grow bigger with increased hydration, the libration amplitude of the carboxyl end amplifies, until onset of dissolution occurs. Our measurements provide the first direct, comprehensive, molecular-level identification of the bioorganic-inorganic interface, showing binding functional groups, geometric constraints, stoichiometry, and dynamics, both for the adsorbed amino acid and the silica surface.
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Affiliation(s)
- Ira Ben Shir
- Schulich Faculty of Chemistry and Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
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Gutmann T, Walaszek B, Yeping X, Wächtler M, del Rosal I, Grünberg A, Poteau R, Axet R, Lavigne G, Chaudret B, Limbach HH, Buntkowsky G. Hydrido-Ruthenium Cluster Complexes as Models for Reactive Surface Hydrogen Species of Ruthenium Nanoparticles. Solid-State 2H NMR and Quantum Chemical Calculations. J Am Chem Soc 2010; 132:11759-67. [DOI: 10.1021/ja104229a] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Torsten Gutmann
- Institut für Physikalische Chemie, Technische Universität Darmstadt, Petersenstrasse 20, D-64287 Darmstadt, Germany, Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, D-10587 Berlin, Germany, Institut für Physikalische Chemie, Friedrich-Schiller Universität Jena, Helmholtzweg 4, D-07743 Jena, Germany, Université de Toulouse, INSA, UPS, CNRS, LPCNO, 135 avenue de Rangueil, F-31077 Toulouse, France, Laboratoire de Chimie de Coordination du CNRS, 205, Route de Narbonne, 31077 Toulouse Cedex 04,
| | - Bernadeta Walaszek
- Institut für Physikalische Chemie, Technische Universität Darmstadt, Petersenstrasse 20, D-64287 Darmstadt, Germany, Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, D-10587 Berlin, Germany, Institut für Physikalische Chemie, Friedrich-Schiller Universität Jena, Helmholtzweg 4, D-07743 Jena, Germany, Université de Toulouse, INSA, UPS, CNRS, LPCNO, 135 avenue de Rangueil, F-31077 Toulouse, France, Laboratoire de Chimie de Coordination du CNRS, 205, Route de Narbonne, 31077 Toulouse Cedex 04,
| | - Xu Yeping
- Institut für Physikalische Chemie, Technische Universität Darmstadt, Petersenstrasse 20, D-64287 Darmstadt, Germany, Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, D-10587 Berlin, Germany, Institut für Physikalische Chemie, Friedrich-Schiller Universität Jena, Helmholtzweg 4, D-07743 Jena, Germany, Université de Toulouse, INSA, UPS, CNRS, LPCNO, 135 avenue de Rangueil, F-31077 Toulouse, France, Laboratoire de Chimie de Coordination du CNRS, 205, Route de Narbonne, 31077 Toulouse Cedex 04,
| | - Maria Wächtler
- Institut für Physikalische Chemie, Technische Universität Darmstadt, Petersenstrasse 20, D-64287 Darmstadt, Germany, Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, D-10587 Berlin, Germany, Institut für Physikalische Chemie, Friedrich-Schiller Universität Jena, Helmholtzweg 4, D-07743 Jena, Germany, Université de Toulouse, INSA, UPS, CNRS, LPCNO, 135 avenue de Rangueil, F-31077 Toulouse, France, Laboratoire de Chimie de Coordination du CNRS, 205, Route de Narbonne, 31077 Toulouse Cedex 04,
| | - Iker del Rosal
- Institut für Physikalische Chemie, Technische Universität Darmstadt, Petersenstrasse 20, D-64287 Darmstadt, Germany, Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, D-10587 Berlin, Germany, Institut für Physikalische Chemie, Friedrich-Schiller Universität Jena, Helmholtzweg 4, D-07743 Jena, Germany, Université de Toulouse, INSA, UPS, CNRS, LPCNO, 135 avenue de Rangueil, F-31077 Toulouse, France, Laboratoire de Chimie de Coordination du CNRS, 205, Route de Narbonne, 31077 Toulouse Cedex 04,
| | - Anna Grünberg
- Institut für Physikalische Chemie, Technische Universität Darmstadt, Petersenstrasse 20, D-64287 Darmstadt, Germany, Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, D-10587 Berlin, Germany, Institut für Physikalische Chemie, Friedrich-Schiller Universität Jena, Helmholtzweg 4, D-07743 Jena, Germany, Université de Toulouse, INSA, UPS, CNRS, LPCNO, 135 avenue de Rangueil, F-31077 Toulouse, France, Laboratoire de Chimie de Coordination du CNRS, 205, Route de Narbonne, 31077 Toulouse Cedex 04,
| | - Romuald Poteau
- Institut für Physikalische Chemie, Technische Universität Darmstadt, Petersenstrasse 20, D-64287 Darmstadt, Germany, Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, D-10587 Berlin, Germany, Institut für Physikalische Chemie, Friedrich-Schiller Universität Jena, Helmholtzweg 4, D-07743 Jena, Germany, Université de Toulouse, INSA, UPS, CNRS, LPCNO, 135 avenue de Rangueil, F-31077 Toulouse, France, Laboratoire de Chimie de Coordination du CNRS, 205, Route de Narbonne, 31077 Toulouse Cedex 04,
| | - Rosa Axet
- Institut für Physikalische Chemie, Technische Universität Darmstadt, Petersenstrasse 20, D-64287 Darmstadt, Germany, Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, D-10587 Berlin, Germany, Institut für Physikalische Chemie, Friedrich-Schiller Universität Jena, Helmholtzweg 4, D-07743 Jena, Germany, Université de Toulouse, INSA, UPS, CNRS, LPCNO, 135 avenue de Rangueil, F-31077 Toulouse, France, Laboratoire de Chimie de Coordination du CNRS, 205, Route de Narbonne, 31077 Toulouse Cedex 04,
| | - Guy Lavigne
- Institut für Physikalische Chemie, Technische Universität Darmstadt, Petersenstrasse 20, D-64287 Darmstadt, Germany, Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, D-10587 Berlin, Germany, Institut für Physikalische Chemie, Friedrich-Schiller Universität Jena, Helmholtzweg 4, D-07743 Jena, Germany, Université de Toulouse, INSA, UPS, CNRS, LPCNO, 135 avenue de Rangueil, F-31077 Toulouse, France, Laboratoire de Chimie de Coordination du CNRS, 205, Route de Narbonne, 31077 Toulouse Cedex 04,
| | - Bruno Chaudret
- Institut für Physikalische Chemie, Technische Universität Darmstadt, Petersenstrasse 20, D-64287 Darmstadt, Germany, Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, D-10587 Berlin, Germany, Institut für Physikalische Chemie, Friedrich-Schiller Universität Jena, Helmholtzweg 4, D-07743 Jena, Germany, Université de Toulouse, INSA, UPS, CNRS, LPCNO, 135 avenue de Rangueil, F-31077 Toulouse, France, Laboratoire de Chimie de Coordination du CNRS, 205, Route de Narbonne, 31077 Toulouse Cedex 04,
| | - Hans-Heinrich Limbach
- Institut für Physikalische Chemie, Technische Universität Darmstadt, Petersenstrasse 20, D-64287 Darmstadt, Germany, Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, D-10587 Berlin, Germany, Institut für Physikalische Chemie, Friedrich-Schiller Universität Jena, Helmholtzweg 4, D-07743 Jena, Germany, Université de Toulouse, INSA, UPS, CNRS, LPCNO, 135 avenue de Rangueil, F-31077 Toulouse, France, Laboratoire de Chimie de Coordination du CNRS, 205, Route de Narbonne, 31077 Toulouse Cedex 04,
| | - Gerd Buntkowsky
- Institut für Physikalische Chemie, Technische Universität Darmstadt, Petersenstrasse 20, D-64287 Darmstadt, Germany, Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, D-10587 Berlin, Germany, Institut für Physikalische Chemie, Friedrich-Schiller Universität Jena, Helmholtzweg 4, D-07743 Jena, Germany, Université de Toulouse, INSA, UPS, CNRS, LPCNO, 135 avenue de Rangueil, F-31077 Toulouse, France, Laboratoire de Chimie de Coordination du CNRS, 205, Route de Narbonne, 31077 Toulouse Cedex 04,
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Waechtler M, Sellin M, Stark A, Akcakayiran D, Findenegg G, Gruenberg A, Breitzke H, Buntkowsky G. 2H and 19F solid-state NMR studies of the ionic liquid [C2Py][BTA]-d10 confined in mesoporous silica materials. Phys Chem Chem Phys 2010; 12:11371-9. [DOI: 10.1039/b926836g] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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37
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Amitay-Rosen T, Vega S. A deuterium MAS NMR study of the local mobility of dissolved methionine and di-alanine at the inner surface of SBA-15. Phys Chem Chem Phys 2010; 12:6763-73. [DOI: 10.1039/b924813g] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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38
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del Rosal I, Gutmann T, Maron L, Jolibois F, Chaudret B, Walaszek B, Limbach HH, Poteau R, Buntkowsky G. DFT 2H quadrupolar coupling constants of ruthenium complexes: a good probe of the coordination of hydrides in conjuction with experiments. Phys Chem Chem Phys 2009; 11:5657-63. [PMID: 19842483 DOI: 10.1039/b822150b] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Transition metal (TM) hydrides are of great interest in chemistry because of their reactivity and their potential as catalysts for hydrogenation reactions. 2H solid-state NMR can be used in order to get information about the local environment of hydrogen atoms, and more particularly the coordination mode of hydrides in such complexes. In this work we will show that it is possible to establish at the level of density functional theory (DFT) a viable methodological strategy that allows the determination of 2H NMR parameters, namely the quadrupolar coupling constant (C(Q)) respectively the quadrupolar splitting (deltanuQ) and the asymmetry parameter (etaQ). The reliability of the method (B3PW91-DFT) and basis set effects have been first evaluated for simple organic compounds (benzene and fluorene). A good correlation between experimental and theoretical values is systematically obtained if the large basis set cc-pVTZ is used for the computations. 2H NMR properties of five mononuclear ruthenium complexes (namely Cp*RuD3(PPh3), Tp*RuD(THT)2, Tp*RuD(D2)(THT) and Tp*RuD(D2)2 and RuD2(D2)2(PCy3)2) which exhibit different ligands and hydrides involved in different coordination modes (terminal-H or eta2-H2), have been calculated and compared to previous experimental data. The results obtained are in excellent agreement with experiments. Although 2H NMR spectra are not always easy to analyze, assistance by quantum chemistry calculations allows unambiguous assignment of the signals of such spectra. As far as experiments can be achieved at very low temperatures in order to avoid dynamic effects, this hybrid theoretical/experimental tool may give useful insights in the context of the characterization of ruthenium surfaces or nanoparticles with solid-state NMR.
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Affiliation(s)
- Iker del Rosal
- Université de Toulouse; INSA, UPS; LPCNO, IRSAMC; 135 avenue de Rangueil, F-31077 Toulouse, France
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39
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Lin YC, Chou HL, Subramanyam Sarma L, Hwang BJ. Stacking Structure of Confined 1-Butanol in SBA-15 Investigated by Solid-State NMR Spectroscopy. Chemistry 2009; 15:10658-65. [DOI: 10.1002/chem.200901636] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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40
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Coasne B, Alba-Simionesco C, Audonnet F, Dosseh G, Gubbins KE. Adsorption and structure of benzene on silica surfaces and in nanopores. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:10648-10659. [PMID: 19670890 DOI: 10.1021/la900984z] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Grand canonical Monte Carlo simulations are used to study the adsorption of benzene on atomistic silica surfaces and in cylindrical nanopores. The effect of temperature and surface chemistry is addressed by studying the adsorption of benzene at 293 and 323 K on both fully and partially hydroxylated silica surfaces or nanopores. We also consider the adsorption of benzene in a cylindrical nanopore of diameter D=3.6 nm and compare our results with those obtained for planar surfaces. The structure of benzene in the vicinity of the planar surface and confined in the cylindrical nanopore is determined by calculating orientational order parameters and examining positional pair correlation functions. The density profiles of adsorbed benzene reveal the strong layering of the adsorbate, which decays with the distance from the silica surface. At a given temperature and at low pressures, the film adsorbed at the fully hydroxylated silica surface is larger than that for the partially hydroxylated silica surface. This result is due to an increase in the density of silanol groups that induces an increase in the polarity of the silica surface, which becomes more attractive for the adsorbate. Our results also suggest that the benzene molecules prefer an orientation in which their ring is nearly perpendicular to the surface when fully hydroxylated surfaces are considered. When partially hydroxylated surfaces are considered, a second preferential orientation is observed where the benzene ring forms an angle of approximately 50 degrees with the silica surface. In this case, the average orientation of the benzene molecules appears disordered as in the bulk phase. These results suggest that determining the experimental orientation of benzene in the vicinity of a silica surface is a difficult task even when the surface chemistry is known. Capillary condensation in the nanopores involves a transition from a partially filled pore (a thin film adsorbed at the pore surface) to a completely filled pore configuration where the confined liquid coexists at equilibrium with the external gas phase. The disordered orientation of the adsorbed benzene molecules in the case of the partially hydroxylated surface favors the condensation of benzene molecules (the condensation pressure for this substrate is lower than that for the fully hydroxylated surface). Finally, these results are consistent with the structural analysis, showing that (1) benzene tends to relax its liquid structure a little in order to optimize its molecular arrangement near the pore wall and (2) the disordering of the liquid structure induced by the surface becomes stronger as the interaction with the pore wall increases.
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Affiliation(s)
- Benoit Coasne
- Institut Charles Gerhardt Montpellier, UMR 5253 CNRS, Université Montpellier 2, ENSCM, Place Eugene Bataillon, 34095 Montpellier Cedex 05, France.
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41
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Walaszek B, Yeping X, Adamczyk A, Breitzke H, Pelzer K, Limbach HH, Huang J, Li H, Buntkowsky G. 2H-solid-state-NMR study of hydrogen adsorbed on catalytically active ruthenium coated mesoporous silica materials. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2009; 35:164-171. [PMID: 19359146 DOI: 10.1016/j.ssnmr.2009.02.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2009] [Revised: 02/17/2009] [Accepted: 02/26/2009] [Indexed: 05/27/2023]
Abstract
(2)H solid-state NMR measurements were performed on three samples of ruthenium nanoparticles synthesized inside two different kinds of mesoporous silica, namely SBA-3 silica materials and SBA-15 functionalized with -COOH groups and loaded with deuterium gas. The line-shape analyses of the spectra reveal the different deuteron species. In all samples a strong -OD signal is found, which shows the catalytic activity of the metal, which activates the D-D bond and deuterates the -SiOH groups through the gas phase, corroborating their usability as catalysts for hydrogenation reactions. At room temperature the mobility of the -Si-OD groups depends on the sample preparation. In addition to the -Si-OD deuterons, the presence of different types of deuterons bound to the metal is revealed. The singly coordinated -Ru-D species exhibit several different quadrupolar couplings, which indicate the presence of several non-equivalent binding sites with differing binding strength. In addition to the dissociated hydrogen species there is also a dihydrogen species -Ru-D(2), which is attributed to defect sites on the surface. It exhibits a fast rotational dynamics at all temperatures. Finally there are also indications of three-fold coordinated surface deuterons and octahedrally coordinated deuterons inside the metal.
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Affiliation(s)
- Bernadeta Walaszek
- Institut für Physikalische und Theoretische Chemie, Freie Universität Berlin, Berlin, Germany
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42
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Amitay-Rosen T, Kababya S, Vega S. A Dynamic Magic Angle Spinning NMR Study of the Local Mobility of Alanine in an Aqueous Environment at the Inner Surface of Mesoporous Materials. J Phys Chem B 2009; 113:6267-82. [DOI: 10.1021/jp810572r] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tal Amitay-Rosen
- Chemical Physics Department, The Weizmann Institute of Science, Rehovot, Israel 76100, Schulich Faculty of Chemisty, Technion, Haifa, Israel 32000
| | - Shifi Kababya
- Chemical Physics Department, The Weizmann Institute of Science, Rehovot, Israel 76100, Schulich Faculty of Chemisty, Technion, Haifa, Israel 32000
| | - Shimon Vega
- Chemical Physics Department, The Weizmann Institute of Science, Rehovot, Israel 76100, Schulich Faculty of Chemisty, Technion, Haifa, Israel 32000
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Lopez del Amo JM, Langer U, Torres V, Buntkowsky G, Vieth HM, Pérez-Torralba M, Sanz D, Claramunt RM, Elguero J, Limbach HH. NMR studies of ultrafast intramolecular proton tautomerism in crystalline and amorphous n,n'-diphenyl-6-aminofulvene-1-aldimine: solid-state, kinetic isotope, and tunneling effects. J Am Chem Soc 2008; 130:8620-32. [PMID: 18597427 DOI: 10.1021/ja801506n] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Using solid-state NMR spectroscopy, we have detected and characterized ultrafast intramolecular proton tautomerism in the N-H-N hydrogen bonds of solid N, N'-diphenyl-6-aminofulvene-1-aldimine ( I) on the microsecond-to-picosecond time scale. (15)N cross-polarization magic-angle-spinning NMR experiments using (1)H decoupling performed on polycrystalline I- (15)N 2 and the related compound N-phenyl- N'-(1,3,4-triazole)-6-aminofulvene-1-aldimine ( II) provided information about the thermodynamics of the tautomeric processes. We found that II forms only a single tautomer but that the gas-phase degeneracy of the two tautomers of I is lifted by solid-state interactions. Rate constants, including H/D kinetic isotope effects (KIEs), on the microsecond-to-picosecond time scale were obtained by measuring and analyzing the longitudinal (15)N and (2)H relaxation times of I- (15)N 2, I- (15)N 2- d 10, and I- (15)N 2- d 1 over a wide temperature range. In addition to the microcrystalline modification, a novel amorphous modification of I was found and studied. In this modification, proton transfer is much faster than in the crystalline form. For both modifications, we observed large H/D KIEs that were temperature-dependent at high temperatures and temperature-independent at low temperatures. These findings are interpreted in terms of a simple quasiclassical tunneling model proposed by Bell and modified by Limbach. We obtained evidence that a reorganization energy is necessary in order to compress the N-H-N hydrogen bond and achieve a molecular configuration in which the barrier for H transfer is reduced and tunneling or an over-barrier reaction can occur.
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Jähnert S, Vaca Chávez F, Schaumann GE, Schreiber A, Schönhoff M, Findenegg GH. Melting and freezing of water in cylindrical silica nanopores. Phys Chem Chem Phys 2008; 10:6039-51. [PMID: 18825292 DOI: 10.1039/b809438c] [Citation(s) in RCA: 150] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Freezing and melting of H(2)O and D(2)O in the cylindrical pores of well-characterized MCM-41 silica materials (pore diameters from 2.5 to 4.4 nm) was studied by differential scanning calorimetry (DSC) and (1)H NMR cryoporometry. Well-resolved DSC melting and freezing peaks were obtained for pore diameters down to 3.0 nm, but not in 2.5 nm pores. The pore size dependence of the melting point depression DeltaT(m) can be represented by the Gibbs-Thomson equation when the existence of a layer of nonfreezing water at the pore walls is taken into account. The DSC measurements also show that the hysteresis connected with the phase transition, and the melting enthalpy of water in the pores, both vanish near a pore diameter D* approximately equal to 2.8 nm. It is concluded that D* represents a lower limit for first-order melting/freezing in the pores. The NMR spin echo measurements show that a transition from low to high mobility of water molecules takes place in all MCM-41 materials, including the one with 2.5 nm pores, but the transition revealed by NMR occurs at a higher temperature than indicated by the DSC melting peaks. The disagreement between the NMR and DSC transition temperatures becomes more pronounced as the pore size decreases. This is attributed to the fact that with decreasing pore size an increasing fraction of the water molecules is situated in the first and second molecular layers next to the pore wall, and these molecules have slower dynamics than the molecules in the core of the pore.
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Affiliation(s)
- S Jähnert
- Institut für Chemie, Stranski-Laboratorium, Technische Universität Berlin, Strasse des 17. Juni 124, Berlin, Germany
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Vyalikh A, Emmler T, Grünberg B, Xu Y, Shenderovich I, Findenegg GH, Limbach HH, Buntkowsky G. Hydrogen Bonding of Water Confined in Controlled-Pore Glass 10-75 Studied by 1H-Solid State NMR. ACTA ACUST UNITED AC 2008. [DOI: 10.1524/zpch.2007.221.1.155] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The adsorption of water in the mesoporous silica material with cylindrical pores of uniform diameter, Controlled Pore Glass 10-75 (CPG), was studied by 1H-MAS solid state NMR spectroscopy. From the NMR spectra it is evident that inside the mesopores of the silica different water environments exist, which are characterized by their individual chemical shift. All observed hydrogen atoms are either surface –SiOH groups or hydrogen bonded water molecules. It is found that there exist some stronger bound water molecules on the surface which are not removable even by heating at a vacuum pump. As a tentative assignment these water molecules are attributed to surface defects or inaccessible cavities in the CPG 10-75. At intermediate water filling levels, the principal signal is a single NMR line with continuously varying chemical shift. This finding is interpreted as the result of a radial water filling mechanism. That is, the filling of the pore grows from the pore surface towards the pore axis. Finally it is shown that water is a sensor for surface and structural inhomogeneity and that a coexistence of inner pore and outer bulk water exists in the system.
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46
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Lopez del Amo JM, Buntkowsky G, Limbach HH, Resa I, Fernandez R, Carmona E. Low-temperature NMR studies of Zn tautomerism and hindered rotations in solid zincocene derivatives. J Phys Chem A 2008; 112:3557-65. [PMID: 18366198 DOI: 10.1021/jp711504g] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Using a combination of NMR methods we have detected and studied fluxional motions in the slip-sandwich structure of solid decamethylzincocene (I, [(eta5-C5Me5)Zn(eta1-C5Me5)]). For comparison, we have also studied the solid iminoacyl derivative [(eta5-C5Me5)Zn(eta1-C(NXyl)C5Me5)] (II). The variable temperature 13C CPMAS NMR spectra of I indicate fast rotations of both Cp* rings in the molecule down to 156 K as well as the presence of an order-disorder phase transition around 210 K. The disorder is shown to be dynamic arising from a fast combined Zn tautomerism and eta1/eta5 reorganization of the Cp* rings between two degenerate states A and B related by a molecular inversion. In the ordered phase, the degeneracy of A and B is lifted; that is, the two rings X and Y are inequivalent, where X exhibits a larger fraction of time in the eta5 state than Y. However, the interconversion is still fast and characterized by a reaction enthalpy of DeltaH = 2.4 kJ mol-1 and a reaction entropy of DeltaS = 4.9 J K-1 mol-1. In order to obtain quantitative kinetic information, variable temperature 2H NMR experiments were performed on static samples of I-d6 and II-d6 between 300 and 100 K, where in each ring one CH3 is replaced by one CD3 group. For II-d6, the 2H NMR line shapes indicate fast CD3 group rotations and a fast "eta5 rotation", corresponding to 72 degrees rotational jumps of the eta5 coordinated Cp* ring. The latter motion becomes slow around 130 K. By line shape analysis, an activation energy of the eta5 rotation of about 21 kJ mol-1 was obtained. 2H NMR line shapes analysis of I-d6 indicates fast CD3 group rotations at all temperatures. Moreover, between 100 and 150 K, a transition from the slow to the fast exchange regime is observed for the 5-fold rotational jumps of both Cp* rings, exhibiting an activation energy of 18 kJ mol-1. This value was corroborated by 2H NMR relaxometry from which additionally the activation energies 6.3 kJ mol-1 and 11.2 kJ mol-1 for the CD3 rotation and the molecular inversion process were determined.
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Affiliation(s)
- Juan Miguel Lopez del Amo
- Institut für Chemie und Biochemie der Freien Universität Berlin, Takustrasse 3, D-14195, Berlin, Germany.
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Schröder F, Esken D, Cokoja M, van den Berg MWE, Lebedev OI, Van Tendeloo G, Walaszek B, Buntkowsky G, Limbach HH, Chaudret B, Fischer RA. Ruthenium Nanoparticles inside Porous [Zn4O(bdc)3] by Hydrogenolysis of Adsorbed [Ru(cod)(cot)]: A Solid-State Reference System for Surfactant-Stabilized Ruthenium Colloids. J Am Chem Soc 2008; 130:6119-30. [DOI: 10.1021/ja078231u] [Citation(s) in RCA: 320] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Felicitas Schröder
- Lehrstuhl für Anorganische Chemie II−Organometallics & Materials, and Lehrstuhl für Technische Chemie, Ruhr-Universität, Universitätsstrasse 150, D-44780 Bochum, Germany, EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium, Institut für Physikalische Chemie, Friedrich-Schiller-Universität, D-07743 Jena, Germany, Physikalische and Theoretische Chemie, Freie Universität, D-11195 Berlin, Germany, and Laboratoire de Chimie de Coordination−CNRS, F-31077 Toulouse Cedex 4, France
| | - Daniel Esken
- Lehrstuhl für Anorganische Chemie II−Organometallics & Materials, and Lehrstuhl für Technische Chemie, Ruhr-Universität, Universitätsstrasse 150, D-44780 Bochum, Germany, EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium, Institut für Physikalische Chemie, Friedrich-Schiller-Universität, D-07743 Jena, Germany, Physikalische and Theoretische Chemie, Freie Universität, D-11195 Berlin, Germany, and Laboratoire de Chimie de Coordination−CNRS, F-31077 Toulouse Cedex 4, France
| | - Mirza Cokoja
- Lehrstuhl für Anorganische Chemie II−Organometallics & Materials, and Lehrstuhl für Technische Chemie, Ruhr-Universität, Universitätsstrasse 150, D-44780 Bochum, Germany, EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium, Institut für Physikalische Chemie, Friedrich-Schiller-Universität, D-07743 Jena, Germany, Physikalische and Theoretische Chemie, Freie Universität, D-11195 Berlin, Germany, and Laboratoire de Chimie de Coordination−CNRS, F-31077 Toulouse Cedex 4, France
| | - Maurits W. E. van den Berg
- Lehrstuhl für Anorganische Chemie II−Organometallics & Materials, and Lehrstuhl für Technische Chemie, Ruhr-Universität, Universitätsstrasse 150, D-44780 Bochum, Germany, EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium, Institut für Physikalische Chemie, Friedrich-Schiller-Universität, D-07743 Jena, Germany, Physikalische and Theoretische Chemie, Freie Universität, D-11195 Berlin, Germany, and Laboratoire de Chimie de Coordination−CNRS, F-31077 Toulouse Cedex 4, France
| | - Oleg I. Lebedev
- Lehrstuhl für Anorganische Chemie II−Organometallics & Materials, and Lehrstuhl für Technische Chemie, Ruhr-Universität, Universitätsstrasse 150, D-44780 Bochum, Germany, EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium, Institut für Physikalische Chemie, Friedrich-Schiller-Universität, D-07743 Jena, Germany, Physikalische and Theoretische Chemie, Freie Universität, D-11195 Berlin, Germany, and Laboratoire de Chimie de Coordination−CNRS, F-31077 Toulouse Cedex 4, France
| | - Gustaaf Van Tendeloo
- Lehrstuhl für Anorganische Chemie II−Organometallics & Materials, and Lehrstuhl für Technische Chemie, Ruhr-Universität, Universitätsstrasse 150, D-44780 Bochum, Germany, EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium, Institut für Physikalische Chemie, Friedrich-Schiller-Universität, D-07743 Jena, Germany, Physikalische and Theoretische Chemie, Freie Universität, D-11195 Berlin, Germany, and Laboratoire de Chimie de Coordination−CNRS, F-31077 Toulouse Cedex 4, France
| | - Bernadeta Walaszek
- Lehrstuhl für Anorganische Chemie II−Organometallics & Materials, and Lehrstuhl für Technische Chemie, Ruhr-Universität, Universitätsstrasse 150, D-44780 Bochum, Germany, EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium, Institut für Physikalische Chemie, Friedrich-Schiller-Universität, D-07743 Jena, Germany, Physikalische and Theoretische Chemie, Freie Universität, D-11195 Berlin, Germany, and Laboratoire de Chimie de Coordination−CNRS, F-31077 Toulouse Cedex 4, France
| | - Gerd Buntkowsky
- Lehrstuhl für Anorganische Chemie II−Organometallics & Materials, and Lehrstuhl für Technische Chemie, Ruhr-Universität, Universitätsstrasse 150, D-44780 Bochum, Germany, EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium, Institut für Physikalische Chemie, Friedrich-Schiller-Universität, D-07743 Jena, Germany, Physikalische and Theoretische Chemie, Freie Universität, D-11195 Berlin, Germany, and Laboratoire de Chimie de Coordination−CNRS, F-31077 Toulouse Cedex 4, France
| | - Hans-Heinrich Limbach
- Lehrstuhl für Anorganische Chemie II−Organometallics & Materials, and Lehrstuhl für Technische Chemie, Ruhr-Universität, Universitätsstrasse 150, D-44780 Bochum, Germany, EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium, Institut für Physikalische Chemie, Friedrich-Schiller-Universität, D-07743 Jena, Germany, Physikalische and Theoretische Chemie, Freie Universität, D-11195 Berlin, Germany, and Laboratoire de Chimie de Coordination−CNRS, F-31077 Toulouse Cedex 4, France
| | - Bruno Chaudret
- Lehrstuhl für Anorganische Chemie II−Organometallics & Materials, and Lehrstuhl für Technische Chemie, Ruhr-Universität, Universitätsstrasse 150, D-44780 Bochum, Germany, EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium, Institut für Physikalische Chemie, Friedrich-Schiller-Universität, D-07743 Jena, Germany, Physikalische and Theoretische Chemie, Freie Universität, D-11195 Berlin, Germany, and Laboratoire de Chimie de Coordination−CNRS, F-31077 Toulouse Cedex 4, France
| | - Roland A. Fischer
- Lehrstuhl für Anorganische Chemie II−Organometallics & Materials, and Lehrstuhl für Technische Chemie, Ruhr-Universität, Universitätsstrasse 150, D-44780 Bochum, Germany, EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium, Institut für Physikalische Chemie, Friedrich-Schiller-Universität, D-07743 Jena, Germany, Physikalische and Theoretische Chemie, Freie Universität, D-11195 Berlin, Germany, and Laboratoire de Chimie de Coordination−CNRS, F-31077 Toulouse Cedex 4, France
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Adamczyk A, Xu Y, Walaszek B, Roelofs F, Pery T, Pelzer K, Philippot K, Chaudret B, Limbach HH, Breitzke H, Buntkowsky G. Solid State and Gas Phase NMR Studies of Immobilized Catalysts and Catalytic Active Nanoparticles. Top Catal 2008. [DOI: 10.1007/s11244-008-9054-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Tang XP, Ng NC, Nguyen H, Mogilevsky G, Wu Y. The molecular dynamics and melting transition of the confined ibuprofen in titania nanotube studied by NMR. Chem Phys Lett 2008. [DOI: 10.1016/j.cplett.2008.01.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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50
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Ratajczyk T, Szymański S. Theory of damped quantum rotation in nuclear magnetic resonance spectra. II. Numerical simulations for the benzene rotor. J Chem Phys 2007; 127:184504. [DOI: 10.1063/1.2785180] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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