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Chai K, Yamaguchi T, Zuo T, Tseng J, Ikeda K, Zhou Y. Structure, Microheterogeneity, and Transport Properties of Ethaline Decoded by X-ray/Neutron Scattering and MD Simulation. J Phys Chem B 2024; 128:7445-7456. [PMID: 39028947 DOI: 10.1021/acs.jpcb.4c02826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/21/2024]
Abstract
Ethaline, a deep eutectic solvent (DES) composed of choline chloride (ChCl)-ethylene glycol (EG) in a 1:2 molar ratio, is garnering significant interest for its wide potential applications. The nature of liquid formation and the structure of H-bonds within ethaline were investigated by X-ray scattering (XRS), neutron scattering (NS), and MD simulations. The sum of the dissociation energy barriers of Ch-EG (3.31 kJ·mol-1) and EG-Cl (4.28 kJ·mol-1) exceeds that of Ch-Cl (5.97 kJ·mol-1). This results in a more pronounced solvation of ChCl by EG compared to ChCl association, facilitating the solubilization of ChCl crystals by EG to form a DES. A partial radial distribution function (PDF) reveals that Cl- solvation is dominated by the hydroxyl group of EG, while the methylene group dominates Ch+ solvation. The spatial distribution function (SDF) shows that the distribution of EG and Cl- around Ch+ partially overlaps with that of the quaternary ammonium group. However, the center of mass distance of Ch-Cl (4.95 Å) is significantly lower than that of Ch-EG (5.65 Å), suggesting a favorable advantage for Cl- in this competition. Chain and ring structure distributions provide direct evidence of the microheterogeneity of ethaline. Hydroxyl groups on the EG promote the formation of a chain structure in ethaline, while methylene groups favor a ring structure. H-bond, carbon H-bond, and Cl- bridge bond restrict Cl- diffusion. This new understanding is crucial for a deeper comprehension of the microstructure of ethaline and for elucidating its mechanisms in applications.
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Affiliation(s)
- Keke Chai
- Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources; Key Laboratory of Salt Lake Resources Chemistry of Qinghai Province; Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining, Qinghai 810008, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Toshio Yamaguchi
- Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources; Key Laboratory of Salt Lake Resources Chemistry of Qinghai Province; Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining, Qinghai 810008, China
| | - Taisen Zuo
- Spallation Neutron Source Science Center (SNSSC), Dongguan, Guangdong 523803, China
| | - Jochi Tseng
- Diffraction and Scattering Division, Japan Synchrotron Radiation Research Institute (JASRI), SPring-8, Sayo-gun Hyogo 679-5198, Japan
| | - Kazutaka Ikeda
- Neutron Industrial Technology Center, Comprehensive Research Organization for Science and Society (CROSS), Tokai, Ibaraki 319-1106, Japan
| | - Yongquan Zhou
- Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources; Key Laboratory of Salt Lake Resources Chemistry of Qinghai Province; Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining, Qinghai 810008, China
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2
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Wilke SK, Benmore CJ, Alderman OLG, Sivaraman G, Ruehl MD, Hawthorne KL, Tamalonis A, Andersson DA, Williamson MA, Weber R. Plutonium oxide melt structure and covalency. NATURE MATERIALS 2024; 23:884-889. [PMID: 38671164 DOI: 10.1038/s41563-024-01883-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 03/26/2024] [Indexed: 04/28/2024]
Abstract
Advances in nuclear power reactors include the use of mixed oxide fuel, containing uranium and plutonium oxides. The high-temperature behaviour and structure of PuO2-x above 1,800 K remain largely unexplored, and these conditions must be considered for reactor design and planning for the mitigation of severe accidents. Here, we measure the atomic structure of PuO2-x through the melting transition up to 3,000 ± 50 K using X-ray scattering of aerodynamically levitated and laser-beam-heated samples, with O/Pu ranging from 1.57 to 1.76. Liquid structural models consistent with the X-ray data are developed using machine-learned interatomic potentials and density functional theory. Molten PuO1.76 contains some degree of covalent Pu-O bonding, signalled by the degeneracy of Pu 5f and O 2p orbitals. The liquid is isomorphous with molten CeO1.75, demonstrating the latter as a non-radioactive, non-toxic, structural surrogate when differences in the oxidation potentials of Pu and Ce are accounted for. These characterizations provide essential constraints for modelling pertinent to reactor safety design.
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Affiliation(s)
- Stephen K Wilke
- Materials Development, Inc., Arlington Heights, IL, USA.
- X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, IL, USA.
| | - Chris J Benmore
- X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, IL, USA
| | - Oliver L G Alderman
- ISIS Neutron & Muon Source, Rutherford Appleton Laboratory, Chilton, Didcot, UK
| | - Ganesh Sivaraman
- Department of Chemical & Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Matthew D Ruehl
- Chemical and Fuel Cycle Technologies Division, Argonne National Laboratory, Lemont, IL, USA
| | - Krista L Hawthorne
- Chemical and Fuel Cycle Technologies Division, Argonne National Laboratory, Lemont, IL, USA
| | | | - David A Andersson
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Mark A Williamson
- Chemical and Fuel Cycle Technologies Division, Argonne National Laboratory, Lemont, IL, USA
| | - Richard Weber
- Materials Development, Inc., Arlington Heights, IL, USA
- X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, IL, USA
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3
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Wong LN, Brunner M, Imberti S, Warr GG, Atkin R. Bulk Nanostructure of Mixtures of Choline Arginate, Choline Lysinate, and Water. J Phys Chem B 2024. [PMID: 38691762 DOI: 10.1021/acs.jpcb.4c01482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2024]
Abstract
Neutron diffraction with empirical potential structure refinement was used to investigate the bulk liquid nanostructure of mixtures of choline arginate (Ch[Arg]), choline lysinate (Ch[Lys]), and water at mole ratios of 1Ch[Arg]:1Ch[Lys]:6H2O (balanced), 1Ch[Arg]:1Ch[Lys]:20H2O (balanced dilute), 3Ch[Arg]:1Ch[Lys]:12H2O (Arg- rich), and 1Ch[Arg]:3Ch[Lys]:12H2O (Lys- rich). The Arg- and Lys- anions tend not to associate due to electrostatic repulsion between charge groups and weak anion-anion attractions. This means that the local ion structures around the anions in these mixtures resemble the parent single-component systems. The bulk liquid nanostructure varies with the Arg-:Lys- ratio. In the Lys--rich mixture (1Ch[Arg]:3Ch[Lys]:12H2O), Lys- side chains cluster into a continuous apolar domain separated from a charged domain of polar groups. In the balanced mixture (1Ch[Arg]:1Ch[Lys]:6H2O), Lys- side chains form discrete apolar aggregates within a continuous polar domain of Arg-, Ch+, and water, and in the Arg--rich mixture (3Ch[Arg]:1Ch[Lys]:12H2O), the distribution of Lys- and Arg- is nearly homogeneous. Finally, in the balance dilute system (1Ch[Arg]:1Ch[Lys]:20H2O), a percolating water domain forms.
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Affiliation(s)
- Lucas N Wong
- School of Molecular Sciences, The University of Western Australia, Crawley, WA 6009, Australia
| | - Manuel Brunner
- School of Molecular Sciences, The University of Western Australia, Crawley, WA 6009, Australia
| | - Silvia Imberti
- UKRI, STFC, ISIS Neutron and Muon Source, Rutherford Appleton Laboratory, Didcot OX11 0QX, United Kingdom
| | - Gregory G Warr
- School of Chemistry and University of Sydney Nano Institute, The University of Sydney, Sydney, NSW 2006, Australia
| | - Rob Atkin
- School of Molecular Sciences, The University of Western Australia, Crawley, WA 6009, Australia
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4
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Wilke SK, Benmore CJ, Menon V, Smith D, Byrn SR, Weber R. Molecular structure of ketoprofen-polyvinylpyrrolidone solid dispersions prepared by different amorphization methods. RSC PHARMACEUTICS 2024; 1:121-131. [PMID: 38646594 PMCID: PMC11024667 DOI: 10.1039/d3pm00038a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 02/25/2024] [Indexed: 04/23/2024]
Abstract
Amorphous solid dispersions (ASDs) are a widely studied formulation approach for improving the bioavailability of poorly water-soluble pharmaceuticals. Yet, a complete understanding remains lacking for how specific processing methods may influence ASDs' molecular structure. We prepare ketoprofen/polyvinylpyrrolidone (KTP/PVP) ASDs, ranging from 0-75 wt% KTP, using five different amorphization techniques: melt quenching, rotary evaporation with vacuum drying, spray drying, and acoustic levitation with either a premixed solution or in situ mixing of separate co-sprayed solutions. The co-spray levitation approach enables on-demand compositional changes in a containerless processing environment, while requiring minimal pharmaceutical material (∼1 mg). The structure of all ASDs are then compared using high-energy X-ray total scattering. X-ray pair distribution functions are similar for most ASDs of a given composition (Rx = 0.4-2.5%), which is consistent with them having similar intramolecular structure. More notably, differences in the X-ray structure factors for the various amorphization routes indicate differing extents of molecular mixing, a direct indication of their relative stability against crystallization. Melt quenching, spray drying, and levitation of premixed solutions exhibit some degree of molecular mixing, while the co-sprayed levitation samples have molecular arrangements like those of KTP/PVP physical mixtures. These findings illustrate how X-ray total scattering can be used to benchmark amorphous forms prepared by different techniques.
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Affiliation(s)
- Stephen K Wilke
- Materials Development, Inc. Evanston 825 Chicago Ave IL 60202 USA
- X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory Argonne IL 60439 USA
| | - Chris J Benmore
- X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory Argonne IL 60439 USA
| | - Vrishank Menon
- Materials Development, Inc. Evanston 825 Chicago Ave IL 60202 USA
| | - Dan Smith
- Improved Pharma West Lafayette IN 47906 USA
| | | | - Richard Weber
- Materials Development, Inc. Evanston 825 Chicago Ave IL 60202 USA
- X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory Argonne IL 60439 USA
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5
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Ma R, Baradwaj N, Nomura KI, Krishnamoorthy A, Kalia RK, Nakano A, Vashishta P. Alkali hydroxide (LiOH, NaOH, KOH) in water: Structural and vibrational properties, including neutron scattering results. J Chem Phys 2024; 160:134309. [PMID: 38568947 DOI: 10.1063/5.0186058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 03/18/2024] [Indexed: 04/05/2024] Open
Abstract
Structural and vibrational properties of aqueous solutions of alkali hydroxides (LiOH, NaOH, and KOH) are computed using quantum molecular dynamics simulations for solute concentrations ranging between 1 and 10M. Element-resolved partial radial distribution functions, neutron and x-ray structure factors, and angular distribution functions are computed for the three hydroxide solutions as a function of concentration. The vibrational spectra and frequency-dependent conductivity are computed from the Fourier transforms of velocity autocorrelation and current autocorrelation functions. Our results for the structure are validated with the available neutron data for 17M concentration of NaOH in water [Semrouni et al., Phys. Chem. Chem. Phys. 21, 6828 (2019)]. We found that the larger ionic radius [rLi+
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Affiliation(s)
- Ruru Ma
- Collaboratory for Advanced Computing and Simulations, University of Southern California, Los Angeles, California 90007-0242, USA
| | - Nitish Baradwaj
- Collaboratory for Advanced Computing and Simulations, University of Southern California, Los Angeles, California 90007-0242, USA
| | - Ken-Ichi Nomura
- Collaboratory for Advanced Computing and Simulations, University of Southern California, Los Angeles, California 90007-0242, USA
| | - Aravind Krishnamoorthy
- Department of Mechanical Engineering, Texas A&M University, College Station, Texas 77843-3123, USA
| | - Rajiv K Kalia
- Collaboratory for Advanced Computing and Simulations, University of Southern California, Los Angeles, California 90007-0242, USA
| | - Aiichiro Nakano
- Collaboratory for Advanced Computing and Simulations, University of Southern California, Los Angeles, California 90007-0242, USA
| | - Priya Vashishta
- Collaboratory for Advanced Computing and Simulations, University of Southern California, Los Angeles, California 90007-0242, USA
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6
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Wilke SK, Al-Rubkhi A, Koyama C, Ishikawa T, Oda H, Topper B, Tsekrekas EM, Möncke D, Alderman OLG, Menon V, Rafferty J, Clark E, Kastengren AL, Benmore CJ, Ilavsky J, Neuefeind J, Kohara S, SanSoucie M, Phillips B, Weber R. Microgravity effects on nonequilibrium melt processing of neodymium titanate: thermophysical properties, atomic structure, glass formation and crystallization. NPJ Microgravity 2024; 10:26. [PMID: 38448495 PMCID: PMC10918169 DOI: 10.1038/s41526-024-00371-x] [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: 11/20/2023] [Accepted: 02/19/2024] [Indexed: 03/08/2024] Open
Abstract
The relationships between materials processing and structure can vary between terrestrial and reduced gravity environments. As one case study, we compare the nonequilibrium melt processing of a rare-earth titanate, nominally 83TiO2-17Nd2O3, and the structure of its glassy and crystalline products. Density and thermal expansion for the liquid, supercooled liquid, and glass are measured over 300-1850 °C using the Electrostatic Levitation Furnace (ELF) in microgravity, and two replicate density measurements were reproducible to within 0.4%. Cooling rates in ELF are 40-110 °C s-1 lower than those in a terrestrial aerodynamic levitator due to the absence of forced convection. X-ray/neutron total scattering and Raman spectroscopy indicate that glasses processed on Earth and in microgravity exhibit similar atomic structures, with only subtle differences that are consistent with compositional variations of ~2 mol. % Nd2O3. The glass atomic network contains a mixture of corner- and edge-sharing Ti-O polyhedra, and the fraction of edge-sharing arrangements decreases with increasing Nd2O3 content. X-ray tomography and electron microscopy of crystalline products reveal substantial differences in microstructure, grain size, and crystalline phases, which arise from differences in the melt processes.
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Affiliation(s)
- Stephen K Wilke
- Materials Development, Inc., Evanston, IL, 60202, USA.
- X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA.
| | | | | | | | - Hirohisa Oda
- Japan Aerospace Exploration Agency, Tsukuba, Japan
| | - Brian Topper
- Center for High Technology Materials, University of New Mexico, Albuquerque, NM, 87106, USA
| | - Elizabeth M Tsekrekas
- Inamori School of Engineering at the New York State College of Ceramics, Alfred University, Alfred, NY, 14802, USA
| | - Doris Möncke
- Inamori School of Engineering at the New York State College of Ceramics, Alfred University, Alfred, NY, 14802, USA
| | - Oliver L G Alderman
- ISIS Neutron & Muon Source, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, UK
| | | | | | - Emma Clark
- Materials Development, Inc., Evanston, IL, 60202, USA
| | - Alan L Kastengren
- X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Chris J Benmore
- X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Jan Ilavsky
- X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Jörg Neuefeind
- Neutron Science Division, Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Shinji Kohara
- National Institute for Materials Science, Tsukuba, Japan
| | | | | | - Richard Weber
- Materials Development, Inc., Evanston, IL, 60202, USA
- X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
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7
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Talewar SK, Pardo LC, Headen TF, Halukeerthi SO, Chikani B, Rosu-Finsen A, Salzmann CG. Hydrophobic hydration of the hydrocarbon adamantane in amorphous ice. Faraday Discuss 2024; 249:69-83. [PMID: 37794776 PMCID: PMC10845010 DOI: 10.1039/d3fd00102d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 06/19/2023] [Indexed: 10/06/2023]
Abstract
Hydrophobic molecules are by definition difficult to hydrate. Previous studies in the area of hydrophobic hydration have therefore often relied on using amphiphilic molecules where the hydrophilic part of a molecule enabled the solubility in liquid water. Here, we show that the hydrophobic adamantane (C10H16) molecule can be fully hydrated through vapour codeposition with water onto a cryogenic substrate at 80 K resulting in the matrix isolation of adamantane in amorphous ice. Using neutron diffraction in combination with the isotopic substitution method and the empirical potential structure refinement technique, we find that the first hydration shell of adamantane is well structured consisting of a hydrogen-bonded cage of 28 water molecules that is also found in cubic structure II clathrate hydrates. The four hexagonal faces of the 51264 cage are situated above the four methine (CH) groups of adamantane whereas the methylene (CH2) groups are positioned below the edges of two adjoining pentagonal faces. The oxygen atoms of the 28 water molecules can be categorised on the basis of symmetry equivalences as twelve A, twelve B and four C oxygens. The water molecules of the first hydration shell display orientations consistent with those expected for a clathrate-hydrate-type cage, but also unfavourable ones with respect to the hydrogen bonding between the water molecules. Annealing the samples at 140 K, which is just below the crystallisation temperature of the matrix, removes the unfavourable orientations and leads to a slight increase in the structural order of the first hydration shell. The very closest water molecules display a tendency for their dipole moments to point towards the adamantane which is attributed to steric effects. Other than this, no significant polarisation effects are observed which is consistent with weak interactions between adamantane and the amorphous ice matrix. FT-IR spectroscopy shows that the incorporation of adamantane into amorphous ice leads to a weakening of the hydrogen bonds. In summary, the matrix-isolation of the highly symmetric adamantane in amorphous ice provides an interesting test case for hydrophobic hydration. Studying the structure and spectroscopic properties of water at the interface with hydrophobic hydrocarbons is also relevant for astrophysical environments, such as comets or the interstellar medium, where amorphous ice and hydrocarbons have been shown to coexist in large quantities.
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Affiliation(s)
- Sukhpreet K Talewar
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK.
| | - Luis Carlos Pardo
- Grup de Caracterització de Materials, Departament de Física, EEBE, Universitat Politècnica de Catalunya, and Barcelona Research Center in Multiscale Science and Engineering, C/Eduard Maristany 10, E-08019 Barcelona, Spain
| | - Thomas F Headen
- ISIS Pulsed Neutron and Muon Source, STFC Rutherford Appleton Laboratory, Harwell Campus, OX11 0QX, UK
| | - Siriney O Halukeerthi
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK.
| | - Bharvi Chikani
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK.
| | - Alexander Rosu-Finsen
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK.
| | - Christoph G Salzmann
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK.
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8
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Hammond O, Morris DC, Bousrez G, Li S, de Campo L, Recsei C, Moir M, Glavatskih S, Rutland MW, Mudring AV. Small-Angle Neutron Scattering Insights into 2-Ethylhexyl Laurate: A Remarkable Bioester. ACS SUSTAINABLE CHEMISTRY & ENGINEERING 2024; 12:1816-1821. [PMID: 38333201 PMCID: PMC10848283 DOI: 10.1021/acssuschemeng.3c04736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 11/17/2023] [Accepted: 11/17/2023] [Indexed: 02/10/2024]
Abstract
Commercial (protiated) samples of the "green" and biodegradable bioester 2-ethylhexyl laurate (2-EHL) were mixed with D-2-EHL synthesized by hydrothermal deuteration, with the mixtures demonstrating bulk structuring in small-angle neutron scattering measurements. Analysis in a polymer scattering framework yielded a radius of gyration (Rg) of 6.5 Å and a Kuhn length (alternatively described as the persistence length or average segment length) of 11.2 Å. Samples of 2-EHL dispersed in acetonitrile formed self-assembled structures exceeding the molecular dimensions of the 2-EHL, with a mean aggregation number (Nagg) of 3.5 ± 0.2 molecules across the tested concentrations. We therefore present structural evidence that this ester can function as a nonionic (co)surfactant. The available surfactant-like conformations appear to enable performance beyond the low calculated hydrophilic-lipophilic balance value of 2.9. Overall, our data offer an explanation for 2-EHL's interfacial adsorption properties via self-assembly, resulting in strong emolliency and lubricity for this sustainable ester-based bio-oil.
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Affiliation(s)
- Oliver
S. Hammond
- Department
of Biological and Chemical Engineering and iNANO, Aarhus University, Aarhus
C 8000, Denmark
- Department
of Materials and Environmental Chemistry, Stockholm University, Stockholm 114 18, Sweden
| | - Daniel C. Morris
- School
of Chemical Engineering, University of New
South Wales, Sydney 2052, Australia
| | - Guillaume Bousrez
- Department
of Biological and Chemical Engineering and iNANO, Aarhus University, Aarhus
C 8000, Denmark
- Department
of Materials and Environmental Chemistry, Stockholm University, Stockholm 114 18, Sweden
| | - Sichao Li
- Division
of Surface and Corrosion Science, School of Engineering Sciences in
Chemistry, Biotechnology and Health, KTH
Royal Institute of Technology, Stockholm 100 44, Sweden
| | - Liliana de Campo
- Australian
Centre for Neutron Scattering, ANSTO, Lucas Heights, New South Wales 2234, Australia
| | - Carl Recsei
- National
Deuteration Facility, ANSTO, Lucas
Heights, New South Wales 2234, Australia
| | - Michael Moir
- National
Deuteration Facility, ANSTO, Lucas
Heights, New South Wales 2234, Australia
| | - Sergei Glavatskih
- Department
of Engineering Design, KTH Royal Institute
of Technology, Stockholm 100 44, Sweden
- Department
of Electromechanical, Systems and Metal Engineering, Ghent University, Ghent 9052, Belgium
- School
of Chemistry, University of New South Wales, Sydney 2052, Australia
| | - Mark W. Rutland
- Division
of Surface and Corrosion Science, School of Engineering Sciences in
Chemistry, Biotechnology and Health, KTH
Royal Institute of Technology, Stockholm 100 44, Sweden
- School
of Chemistry, University of New South Wales, Sydney 2052, Australia
- Laboratoire
de Tribologie et Dynamique des Systèmes, École Central
de Lyon, Lyon 69130, France
| | - Anja-Verena Mudring
- Department
of Biological and Chemical Engineering and iNANO, Aarhus University, Aarhus
C 8000, Denmark
- Department
of Materials and Environmental Chemistry, Stockholm University, Stockholm 114 18, Sweden
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9
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Wong LN, Imberti S, Warr GG, Atkin R. Bulk nanostructure of a deep eutectic solvent with an amphiphilic hydrogen bond donor. Phys Chem Chem Phys 2023; 25:31068-31076. [PMID: 37946570 DOI: 10.1039/d3cp03587e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2023]
Abstract
Neutron diffraction with empirical potential structure refinement (EPSR) show the deep eutectic solvent (DES) 1 : 4 choline chloride : butyric acid is amphiphilically nanostructured. Nanostructure results from solvophobic interactions between the alkyl chains of the butyric acid hydrogen bond donor (HBD) and is retained with addition of 10 wt% water. EPSR fits to the diffraction data is used to produce a three-dimensional model of the liquid which is interrogated to reveal the interactions leading to the solvophobic effect, and therefore nanostructure, in this DES at atomic resolution. The model shows electrostatic and hydrogen bond interactions cause the cation, anion and HBD acid group to cluster into a polar domain, from which the acid alkyl chains are solvophobically excluded into theapolar domain. The polar and apolar domains percolate through the liquid in a bicontinuous sponge-like structure. The effect of adding 10 wt% water is probed, revealing that water molecules are sequestered around the cation and anion within the polar domain, while the neat bulk structure is retained. Alkyl chain packing in the apolar domain becomes slightly better-defined indicating water marginally strengthens solvophobic segregation. These findings reveal bulk self-assembled nanostructure can be produced in DESs via an amphiphilic HBD.
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Affiliation(s)
- Lucas N Wong
- School of Molecular Sciences, The University of Western Australia, Crawley, Perth 6009, Australia.
| | - Silvia Imberti
- STFC, ISIS Neutron and Muon Source, Rutherford Appleton Laboratory, Didcot OX11 0QX, UK
| | - Gregory G Warr
- School of Chemistry and University of Sydney Nano Institute, The University of Sydney, Sydney, NSW 2006, Australia
| | - Rob Atkin
- School of Molecular Sciences, The University of Western Australia, Crawley, Perth 6009, Australia.
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10
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Hammond OS, Bathke EK, Bowron DT, Edler KJ. Trace Water Changes Metal Ion Speciation in Deep Eutectic Solvents: Ce 3+ Solvation and Nanoscale Water Clustering in Choline Chloride-Urea-Water Mixtures. Inorg Chem 2023; 62:18069-18078. [PMID: 37862703 PMCID: PMC10630939 DOI: 10.1021/acs.inorgchem.3c02205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Indexed: 10/22/2023]
Abstract
Eutectic mixtures of choline chloride, urea, and water in deep eutectic solvent (DES)/water molar hydration ratios (w) of 2, 5, and 10, with dissolved cerium salt, were measured using neutron diffraction with isotopic substitution. Structures were modeled using empirical potential structure refinement (EPSR). Ce3+ was found to form highly charged complexes with a mean coordination number between 7 and 8, with the shell containing mostly chloride, followed by water. The shell composition is strongly affected by the molar ratio of dilution, as opposed to the mass or volume fraction, due to the high affinity of Cl- and H2O ligands that displace less favorable interactions with ligands such as urea and choline. The presence of Ce3+ salt disrupted the bulk DES structure slightly, making it more electrolyte-like. The measured coordination shell of choline showed significant discrepancies from the statistical noninteracting distribution, highlighting the nonideality of the blend. Cluster analysis revealed the trace presence of percolating water clusters (25 ≥ n ≥ 2) in solvent compositions of 5 and 10w for the first time.
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Affiliation(s)
- Oliver S. Hammond
- Centre
for Sustainable Chemical Technologies, University
of Bath, Claverton Down, Bath BA2
7AY, U.K.
- Department
of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
| | - Elly K. Bathke
- Centre
for Sustainable Chemical Technologies, University
of Bath, Claverton Down, Bath BA2
7AY, U.K.
- Department
of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
| | - Daniel T. Bowron
- ISIS
Neutron and Muon Source, Science and Technology
Facilities Council, Rutherford Appleton Laboratory, Didcot OX11 0QX, U.K.
| | - Karen J. Edler
- Centre
for Sustainable Chemical Technologies, University
of Bath, Claverton Down, Bath BA2
7AY, U.K.
- Department
of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
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11
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Wilding MC, Benmore C, Headen TF, Di Mino C, Miller TS, Suter TM, Corà F, Clancy AJ, Sella A, McMillan P, Howard CA. The local ordering of polar solvents around crystalline carbon nitride nanosheets in solution. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2023; 381:20220337. [PMID: 37691462 PMCID: PMC10493548 DOI: 10.1098/rsta.2022.0337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 08/03/2023] [Indexed: 09/12/2023]
Abstract
The crystalline graphitic carbon nitride, poly-triazine imide (PTI) is highly unusual among layered materials since it is spontaneously soluble in aprotic, polar solvents including dimethylformamide (DMF). The PTI material consists of layers of carbon nitride intercalated with LiBr. When dissolved, the resulting solutions consist of dissolved, luminescent single to multilayer nanosheets of around 60-125 nm in diameter and Li+ and Br- ions originating from the intercalating salt. To understand this unique solubility, the structure of these solutions has been investigated by high-energy X-ray and neutron diffraction. Although the diffraction patterns are dominated by inter-solvent correlations there are clear differences between the X-ray diffraction data of the PTI solution and the solvent in the 4-6 Å-1 range, with real space differences persisting to at least 10 Å. Structural modelling using both neutron and X-ray datasets as a constraint reveal the formation of distinct, dense solvation shells surrounding the nanoparticles with a layer of Br-close to the PTI-solvent interface. This solvent ordering provides a configuration that is energetically favourable underpinning thermodynamically driven PTI dissolution. This article is part of the theme issue 'Exploring the length scales, timescales and chemistry of challenging materials (Part 2)'.
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Affiliation(s)
- Martin C. Wilding
- UK Catalysis Hub, Research Complex at Harwell, Rutherford Appleton Laboratory, Oxfordshire OX11 0QX, UK
| | - Chris Benmore
- X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, IL, USA
| | - Thomas F. Headen
- ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Oxfordshire OX11 0QX, UK
| | - Camilla Di Mino
- Department of Physics and Astronomy, University College London, London WC1E 6BT, UK
| | - Thomas S. Miller
- Electrochemical Innovation Laboratory, Department of Chemical Engineering, University College London, London WC1E 7JE, UK
| | - Theo M. Suter
- Electrochemical Innovation Laboratory, Department of Chemical Engineering, University College London, London WC1E 7JE, UK
| | - Furio Corà
- Department of Chemistry, University College London, London WC1E 6BT, UK
| | - Adam J. Clancy
- Department of Chemistry, University College London, London WC1E 6BT, UK
| | - Andrea Sella
- Department of Chemistry, University College London, London WC1E 6BT, UK
| | - Paul McMillan
- Department of Chemistry, University College London, London WC1E 6BT, UK
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12
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Hammond OS, Bousrez G, Mehler F, Li S, Shimpi MR, Doutch J, Cavalcanti L, Glavatskih S, Antzutkin ON, Rutland MW, Mudring AV. Molecular Architecture Effects on Bulk Nanostructure in Bis(Orthoborate) Ionic Liquids. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2300912. [PMID: 37395635 DOI: 10.1002/smll.202300912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/11/2023] [Indexed: 07/04/2023]
Abstract
A series of 19 ionic liquids (ILs) based on phosphonium and imidazolium cations of varying alkyl-chain lengths with the orthoborate anions bis(oxalato)borate [BOB]- , bis(mandelato)borate, [BMB]- and bis(salicylato)borate, [BScB]- , are synthesized and studied using small-angle neutron scattering (SANS). All measured systems display nanostructuring, with 1-methyl-3-n-alkyl imidazolium-orthoborates forming clearly bicontinuous L3 spongelike phases when the alkyl chains are longer than C6 (hexyl). L3 phases are fitted using the Teubner and Strey model, and diffusely-nanostructured systems are primarily fitted using the Ornstein-Zernicke correlation length model. Strongly-nanostructured systems have a strong dependence on the cation, with molecular architecture variation explored to determine the driving forces for self-assembly. The ability to form well-defined complex phases is effectively extinguished in several ways: methylation of the most acidic imidazolium ring proton, replacing the imidazolium 3-methyl group with a longer hydrocarbon chain, substitution of [BOB]- by [BMB]- , or exchanging the imidazolium for phosphonium systems, irrespective of phosphonium architecture. The results suggest there is only a small window of opportunity, in terms of molecular amphiphilicity and cation:anion volume matching, for the formation of stable extensive bicontinuous domains in pure bulk orthoborate-based ILs. Particularly important for self-assembly processes appear to be the ability to form H-bonding networks, which offer additional versatility in imidazolium systems.
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Affiliation(s)
- Oliver S Hammond
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, SE-114 18, Sweden
- Department of Biological and Chemical Engineering and iNANO, Aarhus University, Aarhus C, 8000, Denmark
| | - Guillaume Bousrez
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, SE-114 18, Sweden
- Department of Biological and Chemical Engineering and iNANO, Aarhus University, Aarhus C, 8000, Denmark
| | - Filip Mehler
- Division of Surface and Corrosion Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, SE-100 40, Sweden
| | - Sichao Li
- Division of Surface and Corrosion Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, SE-100 40, Sweden
| | - Manishkumar R Shimpi
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, SE-114 18, Sweden
- Chemistry of Interfaces, Luleå University of Technology, Luleå, SE-971 87, Sweden
| | - James Doutch
- ISIS Neutron & Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell-Oxford, OX11 0QX, UK
| | - Leide Cavalcanti
- ISIS Neutron & Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell-Oxford, OX11 0QX, UK
| | - Sergei Glavatskih
- Department of Engineering Design, KTH Royal Institute of Technology, Stockholm, SE-10044, Sweden
- School of Chemistry, University of New South Wales, Sydney, 2052, Australia
- Department of Electromechanical, Systems and Metal Engineering, Ghent University, Ghent, B-9052, Belgium
| | - Oleg N Antzutkin
- Chemistry of Interfaces, Luleå University of Technology, Luleå, SE-971 87, Sweden
| | - Mark W Rutland
- Division of Surface and Corrosion Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, SE-100 40, Sweden
- School of Chemistry, University of New South Wales, Sydney, 2052, Australia
- Bioeconomy and Health Department Materials and Surface Design, RISE Research Institutes of Sweden, Stockholm, SE-114 86, Sweden
- Laboratoire de Tribologie et Dynamique des Systèmes, École Centrale de Lyon, Lyon, 69130, France
| | - Anja-Verena Mudring
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, SE-114 18, Sweden
- Department of Biological and Chemical Engineering and iNANO, Aarhus University, Aarhus C, 8000, Denmark
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13
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Headen TF, Di Mino C, Youngs TG, Clancy AJ. The structure of liquid thiophene from total neutron scattering. Phys Chem Chem Phys 2023; 25:25157-25165. [PMID: 37712384 DOI: 10.1039/d3cp03932c] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/16/2023]
Abstract
The structure of pure liquid thiophene is revealed by using a combination of total neutron scattering experiments with isotopic substitution and molecular simulations via the next generation empirical potential refinement software, Dissolve. In the liquid, thiophene presents three principle local structural motifs within the first solvation shell, in plane and out of the plane of the thiophene ring. Firstly, above/below the ring plane thiophenes present a single H towards the π cloud, due to a combination of electrostatic and dispersion interactions. Secondly, around the ring plane, perpendicular thiophene molecules find 5 preferred sites driven by bifurcated C-H⋯S interactions, showing that hydrogen-sulfur bonding prevails over the charge asymmetry created by the heteroatom. Finally, parallel thiophenes sit above and below the ring, excluded from directly above the ring center and above the sulfur.
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Affiliation(s)
- Thomas F Headen
- ISIS Neutron and Muon Source, STFC Rutherford Appleton Laboratory, Didcot, OX11 0QX, UK.
| | - Camilla Di Mino
- Department of Materials, University of Oxford, 21 Banbury Rd, Oxford, OX2 6NN, UK
- Department of Physics & Astronomy, University College London, Gower St, London WC1E 6BT, UK
| | - Tristan Ga Youngs
- ISIS Neutron and Muon Source, STFC Rutherford Appleton Laboratory, Didcot, OX11 0QX, UK.
| | - Adam J Clancy
- Department of Chemistry, University College London, 20 Gordon St, London, WC1H 0AJ, UK.
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14
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Di Mino C, Clancy AJ, Sella A, Howard CA, Headen TF, Seel AG, Skipper NT. Weak Interactions in Dimethyl Sulfoxide (DMSO)-Tertiary Amide Solutions: The Versatility of DMSO as a Solvent. J Phys Chem B 2023; 127:1357-1366. [PMID: 36752593 PMCID: PMC9940205 DOI: 10.1021/acs.jpcb.2c07155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The structures of equimolar mixtures of the commonly used polar aprotic solvents dimethylformamide (DMF) and dimethylacetamide (DMAc) in dimethyl sulfoxide (DMSO) have been investigated via neutron diffraction augmented by extensive hydrogen/deuterium isotopic substitution. Detailed 3-dimensional structural models of these solutions have been derived from the neutron data via Empirical Potential Structure Refinement (EPSR). The intermolecular center-of-mass (CoM) distributions show that the first coordination shell of the amides comprises ∼13-14 neighbors, of which approximately half are DMSO. In spite of this near ideal coordination shell mixing, the changes to the amide-amide structure are found to be relatively subtle when compared to the pure liquids. Analysis of specific intermolecular atom-atom correlations allows quantitative interpretation of the competition between weak interactions in the solution. We find a hierarchy of formic and methyl C-H···O hydrogen bonds forms the dominant local motifs, with peak positions in the range of 2.5-3.0 Å. We also observe a rich variety of steric and dispersion interactions, including those involving the O═C-N amide π-backbones. This detailed insight into the structural landscape of these important liquids demonstrates the versatility of DMSO as a solvent and the remarkable sensitivity of neutron diffraction, which is critical for understanding weak intermolecular interactions at the nanoscale and thereby tailoring solvent properties to specific applications.
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Affiliation(s)
- Camilla Di Mino
- Department
of Physics and Astronomy, University College
London, Gower Street, LondonWC1E
6BT, U.K.
| | - Adam J. Clancy
- Department
of Chemistry, University College London, 20 Gordon Street, LondonWC1H 0AJ, U.K.
| | - Andrea Sella
- Department
of Chemistry, University College London, 20 Gordon Street, LondonWC1H 0AJ, U.K.
| | - Christopher A. Howard
- Department
of Physics and Astronomy, University College
London, Gower Street, LondonWC1E
6BT, U.K.
| | - Thomas F. Headen
- ISIS
Neutron and Muon Source, Science and Technology
Facilities Council, Rutherford Appleton Laboratory, Harwell Campus, DidcotOX11 0QX, U.K.
| | - Andrew G. Seel
- ISIS
Neutron and Muon Source, Science and Technology
Facilities Council, Rutherford Appleton Laboratory, Harwell Campus, DidcotOX11 0QX, U.K.,E-mail: . Phone: +44 (0)1793 547500
| | - Neal T. Skipper
- Department
of Physics and Astronomy, University College
London, Gower Street, LondonWC1E
6BT, U.K.,E-mail: . Phone: +44 (0)207 679 3526
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15
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Shanks BL, Potoff JJ, Hoepfner MP. Transferable Force Fields from Experimental Scattering Data with Machine Learning Assisted Structure Refinement. J Phys Chem Lett 2022; 13:11512-11520. [PMID: 36469859 DOI: 10.1021/acs.jpclett.2c03163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Deriving transferable pair potentials from experimental neutron and X-ray scattering measurements has been a longstanding challenge in condensed matter physics. State-of-the-art scattering analysis techniques estimate real-space microstructure from reciprocal-space total scattering data by refining pair potentials to obtain agreement between simulated and experimental results. Prior attempts to apply these potentials with molecular simulations have revealed inaccurate predictions of thermodynamic fluid properties. In this Letter, a machine learning assisted structure-inversion method applied to neutron scattering patterns of the noble gases (Ne, Ar, Kr, and Xe) is shown to recover transferable pair potentials that accurately reproduce both microstructure and vapor-liquid equilibria from the triple to critical point. Therefore, it is concluded that a single neutron scattering measurement is sufficient to predict macroscopic thermodynamic properties over a wide range of states and provide novel insight into local atomic forces in dense monatomic systems.
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Affiliation(s)
- Brennon L Shanks
- Department of Chemical Engineering, University of Utah, Salt Lake City, UT84112-9202, United States
| | - Jeffrey J Potoff
- Department of Chemical Engineering and Materials Science, Wayne State University, Detroit, MI48202, United States
| | - Michael P Hoepfner
- Department of Chemical Engineering, University of Utah, Salt Lake City, UT84112-9202, United States
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16
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Hammond OS, Atri R, Bowron DT, Edler KJ. Neutron Diffraction Study of Indole Solvation in Deep Eutectic Systems of Choline Chloride, Malic Acid, and Water. Chemistry 2022; 28:e202200566. [PMID: 35510678 PMCID: PMC9400976 DOI: 10.1002/chem.202200566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Indexed: 11/09/2022]
Abstract
Deep eutectic systems are currently under intense investigation to replace traditional organic solvents in a range of syntheses. Here, indole in choline chloride‐malic acid deep eutectic solvent (DES) was studied as a function of water content, to identify solute interactions with the DES which affect heterocycle reactivity and selectivity, and as a proxy for biomolecule solvation. Empirical Potential Structure Refinement models of neutron diffraction data showed [Cholinium]+ cations associate strongly with the indole π‐system due to electrostatics, whereas malic acid is only weakly associated. Trace water is sequestered into the DES and does not interact strongly with indole. When water is added to the DES, it does not interact with the indole π‐system but is exclusively in‐plane with the heterocyclic rings, forming strong H‐bonds with the ‐NH group, and also weak H‐bonds and thus prominent hydrophobic hydration of the indole aromatic region, which could direct selectivity in reactions.
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Affiliation(s)
- Oliver S. Hammond
- Centre for Sustainable Chemical Technologies and Department of Chemistry University of Bath Claverton Down Bath BA2 7AY U.K
- Current address: Department of Materials and Environmental Chemistry Stockholm University Stockholm Sweden
| | - Ria Atri
- Centre for Sustainable Chemical Technologies and Department of Chemical Engineering University of Bath Claverton Down Bath BA2 7AY U.K
| | - Daniel T. Bowron
- ISIS Neutron and Muon Source Science and Technology Facilities Council Rutherford Appleton Laboratory Didcot OX11 0QX U.K
| | - Karen J. Edler
- Centre for Sustainable Chemical Technologies and Department of Chemistry University of Bath Claverton Down Bath BA2 7AY U.K
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17
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Octahedral oxide glass network in ambient pressure neodymium titanate. Sci Rep 2022; 12:8258. [PMID: 35585110 PMCID: PMC9117677 DOI: 10.1038/s41598-022-12342-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 05/06/2022] [Indexed: 12/05/2022] Open
Abstract
Rare-earth titanates form very fragile liquids that can be made into glasses with useful optical properties. We investigate the atomic structure of 83TiO2-17Nd2O3 glass using pair distribution function (PDF) analysis of X-ray and neutron diffraction with double isotope substitutions for both Ti and Nd. Six total structure factors are analyzed (5 neutron + 1 X-ray) to obtain complementary sensitivities to O and Ti/Nd scattering, and an empirical potential structure refinement (EPSR) provides a structural model consistent with the experimental measurements. Glass density is estimated as 4.72(13) g cm−3, consistent with direct measurements. The EPSR model indicates nearest neighbor interactions for Ti-O at \documentclass[12pt]{minimal}
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\begin{document}$$\overline{r}_{TiO}$$\end{document}r¯TiO = 1.984(11) Å with coordination of \documentclass[12pt]{minimal}
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\begin{document}$$n_{TiO}$$\end{document}nTiO = 5.72(6) and for Nd-O at \documentclass[12pt]{minimal}
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\begin{document}$$\overline{r}_{NdO}$$\end{document}r¯NdO = 2.598(22) Å with coordination of \documentclass[12pt]{minimal}
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\begin{document}$$n_{NdO}$$\end{document}nNdO = 7.70(26), in reasonable agreement with neutron first order difference functions for Ti and Nd. The titanate glass network comprises a mixture of distorted Ti-O5 and Ti-O6 polyhedra connected via 71% corner-sharing and 23% edge-sharing. The O-Ti coordination environments include 15% nonbridging O-Ti1, 51% bridging O-Ti2, and 32% tricluster O-Ti3. This structure is highly unusual for oxide glasses melt-quenched at ambient pressure, as it consists of Ti-Ox predominantly in octahedral (with nearly no tetrahedral) coordination.
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18
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Terban MW, Billinge SJL. Structural Analysis of Molecular Materials Using the Pair Distribution Function. Chem Rev 2022; 122:1208-1272. [PMID: 34788012 PMCID: PMC8759070 DOI: 10.1021/acs.chemrev.1c00237] [Citation(s) in RCA: 54] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Indexed: 12/16/2022]
Abstract
This is a review of atomic pair distribution function (PDF) analysis as applied to the study of molecular materials. The PDF method is a powerful approach to study short- and intermediate-range order in materials on the nanoscale. It may be obtained from total scattering measurements using X-rays, neutrons, or electrons, and it provides structural details when defects, disorder, or structural ambiguities obscure their elucidation directly in reciprocal space. While its uses in the study of inorganic crystals, glasses, and nanomaterials have been recently highlighted, significant progress has also been made in its application to molecular materials such as carbons, pharmaceuticals, polymers, liquids, coordination compounds, composites, and more. Here, an overview of applications toward a wide variety of molecular compounds (organic and inorganic) and systems with molecular components is presented. We then present pedagogical descriptions and tips for further implementation. Successful utilization of the method requires an interdisciplinary consolidation of material preparation, high quality scattering experimentation, data processing, model formulation, and attentive scrutiny of the results. It is hoped that this article will provide a useful reference to practitioners for PDF applications in a wide realm of molecular sciences, and help new practitioners to get started with this technique.
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Affiliation(s)
- Maxwell W. Terban
- Max
Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - Simon J. L. Billinge
- Department
of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, United States
- Condensed
Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, United States
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19
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Kameda Y, Tsutsui K, Amo Y, Usuki T, Ikeda K, Otomo T. Direct Observation of Scattering Angle Dependence of the Inelasticity Effect on the Interference Term Obtained from Time-of-Flight Neutron Diffraction Experiments. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2021. [DOI: 10.1246/bcsj.20210315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Yasuo Kameda
- Faculty of Science, Yamagata University, 1-4-12 Kojirakawa-machi, Yamagata 990-8560, Japan
| | - Kana Tsutsui
- Faculty of Science, Yamagata University, 1-4-12 Kojirakawa-machi, Yamagata 990-8560, Japan
| | - Yuko Amo
- Faculty of Science, Yamagata University, 1-4-12 Kojirakawa-machi, Yamagata 990-8560, Japan
| | - Takeshi Usuki
- Faculty of Science, Yamagata University, 1-4-12 Kojirakawa-machi, Yamagata 990-8560, Japan
| | - Kazutaka Ikeda
- Institute of Material Structure Science, KEK, 1-1 Oho, Ibaraki 305-080, Japan
| | - Toshiya Otomo
- Institute of Material Structure Science, KEK, 1-1 Oho, Ibaraki 305-080, Japan
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20
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Polidori A, Rowlands RF, Zeidler A, Salanne M, Fischer HE, Annighöfer B, Klotz S, Salmon PS. Structure and dynamics of aqueous NaCl solutions at high temperatures and pressures. J Chem Phys 2021; 155:194506. [PMID: 34800945 DOI: 10.1063/5.0067166] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The structure of a concentrated solution of NaCl in D2O was investigated by in situ high-pressure neutron diffraction with chlorine isotope substitution to give site-specific information on the coordination environment of the chloride ion. A broad range of densities was explored by first increasing the temperature from 323 to 423 K at 0.1 kbar and then increasing the pressure from 0.1 to 33.8 kbar at 423 K, thus mapping a cyclic variation in the static dielectric constant of the pure solvent. The experimental work was complemented by molecular dynamics simulations using the TIP4P/2005 model for water, which were validated against the measured equation of state and diffraction results. Pressure-induced anion ordering is observed, which is accompanied by a dramatic increase in the Cl-O and O-O coordination numbers. With the aid of bond-distance resolved bond-angle maps, it is found that the increased coordination numbers do not originate from a sizable alteration to the number of either Cl⋯D-O or O⋯D-O hydrogen bonds but from the appearance of non-hydrogen-bonded configurations. Increased pressure leads to a marked decrease in the self-diffusion coefficients but has only a moderate effect on the ion-water residence times. Contact ion pairs are observed under all conditions, mostly in the form of charge-neutral NaCl0 units, and coexist with solvent-separated Na+-Na+ and Cl--Cl- ion pairs. The exchange of water molecules with Na+ adopts a concerted mechanism under ambient conditions but becomes non-concerted as the state conditions are changed. Our findings are important for understanding the role of extreme conditions in geochemical processes.
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Affiliation(s)
- Annalisa Polidori
- Department of Physics, University of Bath, Bath BA2 7AY, United Kingdom
| | - Ruth F Rowlands
- Department of Physics, University of Bath, Bath BA2 7AY, United Kingdom
| | - Anita Zeidler
- Department of Physics, University of Bath, Bath BA2 7AY, United Kingdom
| | - Mathieu Salanne
- Sorbonne Université, CNRS, Physico-Chimie des Électrolytes et Nanosystèmes Interfaciaux, F-75005 Paris, France
| | - Henry E Fischer
- Institut Laue Langevin, 71 Avenue des Martyrs, 38042 Grenoble Cedex 9, France
| | - Burkhard Annighöfer
- Université Paris-Saclay, Laboratoire Léon Brillouin, CEA-CNRS, Saclay, 91191 Gif-sur-Yvette Cedex, France
| | - Stefan Klotz
- Sorbonne Université, UMR 7590, IMPMC, F-75252 Paris, France
| | - Philip S Salmon
- Department of Physics, University of Bath, Bath BA2 7AY, United Kingdom
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21
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Balacescu L, Brandl G, Radulescu A. Separation of the inelastic and elastic scattering in time-of-flight mode on the pinhole small-angle neutron scattering diffractometer K-WS-2. J Appl Crystallogr 2021; 54:1217-1224. [PMID: 34429724 PMCID: PMC8366428 DOI: 10.1107/s1600576721006610] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 06/24/2021] [Indexed: 02/19/2023] Open
Abstract
To study and control the incoherent inelastic background in small-angle neutron scattering, which makes a significant contribution to the detected scattering from hydrocarbon systems, the KWS-2 small-angle neutron scattering diffractometer operated by the Jülich Centre for Neutron Science (JCNS) at Heinz-Maier Leibnitz Zentrum (MLZ), Garching, Germany, was equipped with a secondary single-disc chopper that is placed in front of the sample stage. This makes it possible to record in time-of-flight mode the scattered neutrons in the high-Q regime of the instrument (i.e. short incoming wavelengths and detection distances) and to discard the inelastic component from the measured data. Examples of measurements on different materials routinely used as standard samples, sample containers and solvents in the experiments at KWS-2 are presented. When only the elastic region of the spectrum is used in the data-reduction procedure, a decrease of up to two times in the incoherent background of the experimentally measured scattering cross section may be obtained. The proof of principle is demonstrated on a solution of bovine serum albumin in D2O.
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Affiliation(s)
- Livia Balacescu
- Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ), Forschungszentrum Jülich GmbH, Lichtenbergstrasse 1, Garching, 85747, Germany
- Physikalisches Institut (IA), Rheinisch-Westfälische Technische Hochschule (RWTH), Otto-Blumenthal Strasse, Aachen, 52074, Germany
| | - Georg Brandl
- Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ), Forschungszentrum Jülich GmbH, Lichtenbergstrasse 1, Garching, 85747, Germany
| | - Aurel Radulescu
- Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ), Forschungszentrum Jülich GmbH, Lichtenbergstrasse 1, Garching, 85747, Germany
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22
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Peterson PF, Olds D, McDonnell MT, Page K. Illustrated formalisms for total scattering data: a guide for new practitioners. J Appl Crystallogr 2021; 54:317-332. [PMID: 33833656 PMCID: PMC7941302 DOI: 10.1107/s1600576720015630] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 11/27/2020] [Indexed: 11/14/2022] Open
Abstract
This article provides a detailed and visual presentation of the derivations of and relationships between many of the commonly employed functional forms of real- and reciprocal-space data employed by the worldwide total scattering community. The total scattering method is the simultaneous study of both the real- and reciprocal-space representations of diffraction data. While conventional Bragg-scattering analysis (employing methods such as Rietveld refinement) provides insight into the average structure of the material, pair distribution function (PDF) analysis allows for a more focused study of the local atomic arrangement of a material. Generically speaking, a PDF is generated by Fourier transforming the total measured reciprocal-space diffraction data (Bragg and diffuse) into a real-space representation. However, the details of the transformation employed and, by consequence, the resultant appearance and weighting of the real-space representation of the system can vary between different research communities. As the worldwide total scattering community continues to grow, these subtle differences in nomenclature and data representation have led to conflicting and confusing descriptions of how the PDF is defined and calculated. This paper provides a consistent derivation of many of these different forms of the PDF and the transformations required to bridge between them. Some general considerations and advice for total scattering practitioners in selecting and defining the appropriate choice of PDF in their own research are presented. This contribution aims to benefit people starting in the field or trying to compare their results with those of other researchers.
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Affiliation(s)
- Peter F Peterson
- Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.,Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Daniel Olds
- National Synchrotron Light Source-II, Brookhaven National Laboratory, Upton, NY, USA
| | - Marshall T McDonnell
- Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Katharine Page
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.,Materials Science and Engineering Department, University of Tennessee, Knoxville, TN, USA
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Hammond OS, Atri RS, Bowron DT, de Campo L, Diaz-Moreno S, Keenan LL, Doutch J, Eslava S, Edler KJ. Structural evolution of iron forming iron oxide in a deep eutectic-solvothermal reaction. NANOSCALE 2021; 13:1723-1737. [PMID: 33428701 DOI: 10.1039/d0nr08372k] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Deep eutectic solvents (DES) and their hydrated mixtures are used for solvothermal routes towards greener functional nanomaterials. Here we present the first static structural and in situ studies of the formation of iron oxide (hematite) nanoparticles in a DES of choline chloride : urea where xurea = 0.67 (aka. reline) as an exemplar solvothermal reaction, and observe the effects of water on the reaction. The initial speciation of Fe3+ in DES solutions was measured using extended X-ray absorption fine structure (EXAFS), while the atomistic structure of the mixture was resolved from neutron and X-ray diffraction and empirical potential structure refinement (EPSR) modelling. The reaction was monitored using in situ small-angle neutron scattering (SANS), to determine mesoscale changes, and EXAFS, to determine local rearrangements of order around iron ions. It is shown that iron salts form an octahedral [Fe(L)3(Cl)3] complex where (L) represents various O-containing ligands. Solubilised Fe3+ induced subtle structural rearrangements in the DES due to abstraction of chloride into complexes and distortion of H-bonding around complexes. EXAFS suggests the complex forms [-O-Fe-O-] oligomers by reaction with the products of thermal hydrolysis of urea, and is thus pseudo-zero-order in iron. In the hydrated DES, the reaction, nucleation and growth proceeds rapidly, whereas in the pure DES, the reaction initially proceeds quickly, but suddenly slows after 5000 s. In situ SANS and static small-angle X-ray scattering (SAXS) experiments reveal that nanoparticles spontaneously nucleate after 5000 s of reaction time in the pure DES before slow growth. Contrast effects observed in SANS measurements suggest that hydrated DES preferentially form 1D particle morphologies because of choline selectively capping surface crystal facets to direct growth along certain axes, whereas capping is restricted by the solvent structure in the pure DES.
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Affiliation(s)
- Oliver S Hammond
- Department of Chemistry and Centre for Doctoral Training in Sustainable Chemical Technologies, University of Bath, Claverton Down, Bath BA2 7AY, UK.
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25
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Brunner M, Imberti S, Warr GG, Atkin R. Liquid Structure of Single and Mixed Cation Alkylammonium Bromide Urea Deep Eutectic Solvents. J Phys Chem B 2020; 124:8651-8664. [PMID: 32845151 DOI: 10.1021/acs.jpcb.0c06380] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The liquid structures of three alkyl ammonium bromide and urea DESs, ethylammonium bromide:urea (1:1), butylammonium bromide:urea (1:1), and ethylammonium bromide/butylammonium bromide:urea (0.5:0.5:1), have been studied using small-angle neutron diffraction with H/D substituted sample contrasts. The diffraction data was fit using empirical potential structure refinement (EPSR). An amphiphilic nanostructure was found in all DESs due to cation alkyl chains being solvophobically excluded from charged domains, and due to clustering together. The polar domain was continuous in all three DESs, whereas the apolar domain was continuous for the butylammonium DES and in the mixed DES, but not the ethylammonium DES. This is attributed to solvophobic interactions being weaker for the short ethyl chain. Surprisingly, the urea also forms large clusters in all three DESs. In ethylammonium bromide:urea (1:1), urea-urea orientations are mainly perpendicular, but in butylammonium bromide:urea (1:1) and the mixed system in-plane and perpendicular arrangements are found. The liquid nanostructures found in this work, especially for the ethylammonium DES, are different from those found previously for the corresponding DESs formed using glycerol, revealing that the DES amphiphilic nanostructure is sensitive to the nature of the HBD (hydrogen bond donor).
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Affiliation(s)
- Manuel Brunner
- School of Molecular Sciences, The University of Western Australia, 35 Stirling Highway, Perth, Western Australia 6009, Australia
| | - Silvia Imberti
- STFC, Rutherford Appleton Laboratory, Didcot OX11 0QX, United Kingdom
| | - Gregory G Warr
- School of Chemistry and University of Sydney Nano Institute, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Rob Atkin
- School of Molecular Sciences, The University of Western Australia, 35 Stirling Highway, Perth, Western Australia 6009, Australia
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26
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Hammond OS, Moura L, Level G, Imberti S, Holbrey JD, Blesic M. Hydration of sulfobetaine dizwitterions as a function of alkyl spacer length. Phys Chem Chem Phys 2020; 22:16040-16050. [PMID: 32706356 DOI: 10.1039/d0cp02654a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The solvation and structure of bolaform dizwitterions containing two sulfobetaine moieties in concentrated aqueous solution were determined using neutron diffraction with isotopic substitution (NDIS) combined with modelling of the measured structure factors using Empirical Potential Structure Refinement (EPSR). Strongly directional local hydration was observed in the polar regimes of the dizwitterions with 48-52 water molecules shared between dizwitterion molecules in a first shell water network around each zwitterion pair. Overall, the double zwitterions were highly hydrated, providing experimental evidence in support of the potential formation of protein-resistant hydration layers at zwitterion-water interfaces.
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Affiliation(s)
- Oliver S Hammond
- The QUILL Research Centre, School of Chemistry and Chemical Engineering, Queen's University Belfast, Belfast, BT9 5AG, Northern Ireland, UK.
| | - Leila Moura
- The QUILL Research Centre, School of Chemistry and Chemical Engineering, Queen's University Belfast, Belfast, BT9 5AG, Northern Ireland, UK.
| | - Gaelle Level
- The QUILL Research Centre, School of Chemistry and Chemical Engineering, Queen's University Belfast, Belfast, BT9 5AG, Northern Ireland, UK.
| | - Silvia Imberti
- ISIS, Rutherford Appleton Laboratory, Harwell Science & Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - John D Holbrey
- The QUILL Research Centre, School of Chemistry and Chemical Engineering, Queen's University Belfast, Belfast, BT9 5AG, Northern Ireland, UK.
| | - Marijana Blesic
- The QUILL Research Centre, School of Chemistry and Chemical Engineering, Queen's University Belfast, Belfast, BT9 5AG, Northern Ireland, UK.
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27
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Di Gioacchino M, Ricci MA, Imberti S, Holzmann N, Bruni F. Hydration and aggregation of a simple amino acid: The case of glycine. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2019.112407] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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28
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Laurent H, Soper AK, Dougan L. Trimethylamine N-oxide (TMAO) resists the compression of water structure by magnesium perchlorate: terrestrial kosmotrope vs. Martian chaotrope. Phys Chem Chem Phys 2020; 22:4924-4937. [PMID: 32091074 DOI: 10.1039/c9cp06324b] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Neutron diffraction and computational modelling provide insight into water structure.
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Affiliation(s)
| | - Alan K. Soper
- ISIS Facility
- STFC Rutherford Appleton Laboratory
- Didcot
- UK
| | - Lorna Dougan
- Department of Physics and Astronomy
- University of Leeds
- Leeds
- UK
- Astbury Centre for Structural and Molecular Biology
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29
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Moura L, Gilmore M, Callear SK, Youngs TGA, Holbrey JD. Solution structure of propane and propene dissolved in the ionic liquid 1-butyl-3-methylimidazolium bis{(trifluoromethyl)sulfonyl}imide from neutron diffraction with H/D substitution and empirical potential structure refinement modelling. Mol Phys 2019. [DOI: 10.1080/00268976.2019.1649495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Leila Moura
- QUILL Research Centre, School of Chemistry and Chemical Engineering, Queen's University Belfast, Belfast, UK
| | - Mark Gilmore
- QUILL Research Centre, School of Chemistry and Chemical Engineering, Queen's University Belfast, Belfast, UK
| | | | | | - John D. Holbrey
- QUILL Research Centre, School of Chemistry and Chemical Engineering, Queen's University Belfast, Belfast, UK
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30
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Shephard JJ, Evans JSO, Salzmann CG. Local structure and orientational ordering in liquid bromoform. Mol Phys 2019. [DOI: 10.1080/00268976.2019.1648897] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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31
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Basma N, Cullen PL, Clancy AJ, Shaffer MSP, Skipper NT, Headen TF, Howard CA. The liquid structure of the solvents dimethylformamide (DMF) and dimethylacetamide (DMA). Mol Phys 2019. [DOI: 10.1080/00268976.2019.1649494] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- N. Basma
- Department of Physics & Astronomy, University College London, London, UK
- Department of Chemistry and Department of Materials, Imperial College London, London, UK
| | - P. L. Cullen
- Department of Chemical Engineering, University College London, London, UK
| | - A. J. Clancy
- Department of Physics & Astronomy, University College London, London, UK
- Department of Chemistry, University College London, London, UK
| | - M. S. P. Shaffer
- Department of Chemistry and Department of Materials, Imperial College London, London, UK
| | - N. T. Skipper
- Department of Physics & Astronomy, University College London, London, UK
| | - T. F. Headen
- ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot, UK
| | - C. A. Howard
- Department of Physics & Astronomy, University College London, London, UK
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32
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33
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Headen TF. Temperature dependent structural changes in liquid benzene studied using neutron diffraction. Mol Phys 2019. [DOI: 10.1080/00268976.2019.1631496] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Thomas F. Headen
- ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot, Oxon, UK
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34
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Cabrillo C, Barroso-Bujans F, Cerveny S, Fernandez-Perea R, Fernandez-Alonso F, Bowron D, Bermejo FJ. Two-dimensional ordering in 1-propanol-graphite-oxide intercalates: isotopic effects. Mol Phys 2019. [DOI: 10.1080/00268976.2019.1638978] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
| | - Fabienne Barroso-Bujans
- Centro de Física de Materiales (CSIC-UPV/EHU)-MPC, San Sebastian, Spain
- Donostia International Physics Center (DIPC), San Sebastian, Spain
- IKERBASQUE – Basque Foundation for Science, Bilbao, Spain
| | - Silvina Cerveny
- Centro de Física de Materiales (CSIC-UPV/EHU)-MPC, San Sebastian, Spain
- Donostia International Physics Center (DIPC), San Sebastian, Spain
| | | | | | - Daniel Bowron
- ISIS Pulsed Neutron & Muon Source, Rutherford Appleton Laboratory, Didcot, UK
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35
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Semrouni D, Wang HW, Clark SB, Pearce CI, Page K, Schenter G, Wesolowski DJ, Stack AG, Clark AE. Resolving local configurational contributions to X-ray and neutron radial distribution functions within solutions of concentrated electrolytes - a case study of concentrated NaOH. Phys Chem Chem Phys 2019; 21:6828-6838. [PMID: 30620014 DOI: 10.1039/c8cp06802j] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Extreme conditions of complex materials often lead to a manifold of local environments that challenge characterization and require new advances at the intersection of modern experimental and theoretical techniques. In this contribution, highly caustic and viscous aqueous NaOD solutions were characterized with a combination of X-ray and neutron radial distribution function (RDF) analyses, molecular dynamics simulations and sub-ensemble analysis. While this system has been the topic of some study, the current work expands upon the state of knowledge regarding the extent to which water is perturbed within this chemically extreme solution. Further, we introduce analyses that goes beyond merely identifying the different local environments (ion solvation and coordination environments) that are present, but toward understanding their relative contributions to the ensemble solution RDF. This integrated approach yields unique insight into the experimental sensitivity of RDFs to changes in local geometries, the composition of solvation environments about ions, and the challenge of experimentally differentiating the ensemble of all superimposed local environments-a feature of increasing importance within the extreme condition of high ionic strength.
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Affiliation(s)
- David Semrouni
- Department of Chemistry and the Materials Science and Engineering Program, Washington State University, Pullman, WA 99164, USA.
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36
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Kameda Y, Amo Y, Usuki T, Umebayashi Y, Ikeda K, Otomo T. Neutron Diffraction Study on Partial Pair Correlation Functions of Water at Ambient Temperature. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2018. [DOI: 10.1246/bcsj.20180205] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Yasuo Kameda
- Department of Material and Biological Chemistry, Faculty of Science, Yamagata University, Yamagata 990-8560, Japan
| | - Yuko Amo
- Department of Material and Biological Chemistry, Faculty of Science, Yamagata University, Yamagata 990-8560, Japan
| | - Takeshi Usuki
- Department of Material and Biological Chemistry, Faculty of Science, Yamagata University, Yamagata 990-8560, Japan
| | - Yasuhiro Umebayashi
- Graduate School of Science and Technology, Niigata University, Niigata 950-2181, Japan
| | - Kazutaka Ikeda
- Institute of Material Structure Science, KEK, Tsukuba, Ibaraki 305-080, Japan
| | - Toshiya Otomo
- Institute of Material Structure Science, KEK, Tsukuba, Ibaraki 305-080, Japan
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37
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Basma NS, Headen TF, Shaffer MSP, Skipper NT, Howard CA. Local Structure and Polar Order in Liquid N-Methyl-2-pyrrolidone (NMP). J Phys Chem B 2018; 122:8963-8971. [DOI: 10.1021/acs.jpcb.8b08020] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Nadir S. Basma
- Department of Chemistry, Imperial College London, South Kensington, London SW7 2AZ, U.K
- Department of Physics and Astronomy, University College London, London WC1E 6BT, U.K
| | - Thomas F. Headen
- ISIS Neutron and Muon Source, Rutherford Appleton Laboratory, Harwell Campus, Didcot OX11 0QX, Oxfordshire, U.K
| | - Milo S. P. Shaffer
- Department of Chemistry, Imperial College London, South Kensington, London SW7 2AZ, U.K
| | - Neal T. Skipper
- Department of Physics and Astronomy, University College London, London WC1E 6BT, U.K
| | - Christopher A. Howard
- Department of Physics and Astronomy, University College London, London WC1E 6BT, U.K
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38
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Lenton S, Rhys NH, Towey JJ, Soper AK, Dougan L. Temperature-Dependent Segregation in Alcohol-Water Binary Mixtures Is Driven by Water Clustering. J Phys Chem B 2018; 122:7884-7894. [PMID: 30039970 DOI: 10.1021/acs.jpcb.8b03543] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Previous neutron scattering work, combined with computer simulated structure analysis, has established that binary mixtures of methanol and water partially segregate into water-rich and alcohol-rich components. It has furthermore been noted that, between methanol mole fractions of 0.27 and 0.54, both components, water and methanol, simultaneously form percolating clusters. This partial segregation is enhanced with decreasing temperature. The mole fraction of 0.27 also corresponds to the point of maximum excess entropy for ethanol-water mixtures. Here, we study the degree of molecular segregation in aqueous ethanol solutions at a mole fraction of 0.27 and compare it with that in methanol-water solutions at the same concentration. Structural information is extracted for these solutions using neutron diffraction coupled with empirical potential structure refinement. We show that ethanol, like methanol, bi-percolates at this concentration and that, in a similar manner to methanol, alcohol segregation, as measured by the proximity of neighboring methyl sidechains, is increased upon cooling the solution. Water clustering is found to be significantly enhanced in both alcohol solutions compared to the water clustering that occurs for random, hard sphere-like, mixing with no hydrogen bonds between molecules. Alcohol clustering via the hydrophobic groups is, on the other hand, only slightly sensitive to the water hydrogen bond network. These results support the idea that it is the water clustering that drives the partial segregation of the two components, and hence the observed excess entropy of mixing.
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Affiliation(s)
- Samuel Lenton
- School of Physics and Astronomy , University of Leeds , Leeds LS2 9JT , U.K
| | - Natasha H Rhys
- School of Physics and Astronomy , University of Leeds , Leeds LS2 9JT , U.K
| | - James J Towey
- School of Physics and Astronomy , University of Leeds , Leeds LS2 9JT , U.K
| | - Alan K Soper
- ISIS Facility , STFC Rutherford Appleton Laboratory , Harwell Campus , Didcot OX11 0QX , U.K
| | - Lorna Dougan
- School of Physics and Astronomy , University of Leeds , Leeds LS2 9JT , U.K
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39
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Playford HY, Whale TF, Murray BJ, Tucker MG, Salzmann CG. Analysis of stacking disorder in ice I using pair distribution functions. J Appl Crystallogr 2018. [DOI: 10.1107/s1600576718009056] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Stacking-disordered materials display crystalline order in two dimensions but are disordered along the direction in which layered structural motifs are stacked. Countless examples of stacking disorder exist, ranging from close-packed metals, ice I and diamond to open-framework materials and small-molecule pharmaceuticals. In general, the presence of stacking disorder can have profound consequences for the physical and chemical properties of a material. Traditional analyses of powder diffraction data are often complicated by the presence of memory effects in the stacking sequences. Here it is shown that experimental pair distribution functions of stacking-disordered ice I can be used to determine local information on the fractions of cubic and hexagonal stacking. Ice is a particularly challenging material in this respect, since both the stacking disorder and the orientational disorder of the water molecules need to be described. Memory effects are found to contribute very little to the pair distribution functions, and consequently, the analysis of pair distribution functions is the method of choice for characterizing stacking-disordered samples with complicated and high-order memory effects. In the context of this work, the limitations of current structure-reconstruction approaches are also discussed.
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40
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Gilmore M, Moura LM, Turner AH, Swadźba-Kwaśny M, Callear SK, McCune JA, Scherman OA, Holbrey JD. A comparison of choline:urea and choline:oxalic acid deep eutectic solvents at 338 K. J Chem Phys 2018; 148:193823. [DOI: 10.1063/1.5010246] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
- Mark Gilmore
- School of Chemistry and Chemical Engineering, The Queen’s University of Belfast, Belfast BT9 5AG, Northern Ireland,
United Kingdom
| | - Leila M. Moura
- School of Chemistry and Chemical Engineering, The Queen’s University of Belfast, Belfast BT9 5AG, Northern Ireland,
United Kingdom
| | - Adam H. Turner
- School of Chemistry and Chemical Engineering, The Queen’s University of Belfast, Belfast BT9 5AG, Northern Ireland,
United Kingdom
| | - Małgorzata Swadźba-Kwaśny
- School of Chemistry and Chemical Engineering, The Queen’s University of Belfast, Belfast BT9 5AG, Northern Ireland,
United Kingdom
| | - Samantha K. Callear
- ISIS, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE,
United Kingdom
| | - Jade A. McCune
- Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge, Lensfield Road,
Cambridge CB2 1EW, United Kingdom
| | - Oren A. Scherman
- Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge, Lensfield Road,
Cambridge CB2 1EW, United Kingdom
| | - John D. Holbrey
- School of Chemistry and Chemical Engineering, The Queen’s University of Belfast, Belfast BT9 5AG, Northern Ireland,
United Kingdom
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41
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Perrin A, Goodwin MJ, Callear S, Soper AK, Musa OM, Steed JW. Structures of a Clathrate Hydrate Former, Inhibitor, and Synergist in Water. J Phys Chem B 2018; 122:4901-4912. [PMID: 29678107 DOI: 10.1021/acs.jpcb.8b02762] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
SANS studies are reported for aqueous THF at the 1:17 clathrate hydrate-forming composition and on aqueous solutions of the synergist 2-butoxyethanol. Addition of the clathrate hydrate inhibitor polyvinylcaprolactam and a dimeric model compound, 1,3-bis(caprolactamyl)butane, show that the inhibitors do not significantly affect the solution structures of these two important species in clathrate hydrate formation and inhibition. The SANS studies show that 1,3-bis(caprolactamyl)butane is a good model for polyvinylcaprolactam, and both the polymer and model compound exhibit hydrogen bonding interactions with water but do not interact significantly with 2-butoxyethanol in aqueous solution.
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Affiliation(s)
- Andrea Perrin
- Department of Chemistry , Durham University , Lower Mountjoy, Stockton Road , Durham DH1 3LE , United Kingdom
| | - Melissa J Goodwin
- Department of Chemistry , Durham University , Lower Mountjoy, Stockton Road , Durham DH1 3LE , United Kingdom
| | - Samantha Callear
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Campus , Didcot , Oxon OX11 0QX , United Kingdom
| | - Alan K Soper
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Campus , Didcot , Oxon OX11 0QX , United Kingdom
| | - Osama M Musa
- Ashland LLC , 1005 Route 202/206 , Bridgewater , New Jersey 08807 , United States
| | - Jonathan W Steed
- Department of Chemistry , Durham University , Lower Mountjoy, Stockton Road , Durham DH1 3LE , United Kingdom
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42
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Ingram DJ, Headen TF, Skipper NT, Callear SK, Billing M, Sella A. Dihydrogen vs. hydrogen bonding in the solvation of ammonia borane by tetrahydrofuran and liquid ammonia. Phys Chem Chem Phys 2018; 20:12200-12209. [DOI: 10.1039/c7cp08220g] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The solvation structures of two systems rich in hydrogen and dihydrogen bonding interactions have been studied in detail experimentally through neutron diffraction with hydrogen/deuterium isotopic substitution.
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Affiliation(s)
- David J. Ingram
- Department of Physics & Astronomy
- University College London
- London
- UK
- Department of Chemistry
| | | | - Neal T. Skipper
- Department of Physics & Astronomy
- University College London
- London
- UK
- London Centre for Nanotechnology
| | | | | | - Andrea Sella
- Department of Chemistry
- University College London
- London
- UK
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43
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Headen TF, Cullen PL, Patel R, Taylor A, Skipper NT. The structures of liquid pyridine and naphthalene: the effects of heteroatoms and core size on aromatic interactions. Phys Chem Chem Phys 2018; 20:2704-2715. [DOI: 10.1039/c7cp06689a] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Spatial and orientational structures of liquid naphthalene and pyridine revealed using neutron scattering combined with empirical potential structure refinement.
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Affiliation(s)
- T. F. Headen
- ISIS Neutron Facility, STFC Rutherford Appleton Laboratory, Harwell Campus
- Didcot
- UK
| | - P. L. Cullen
- University College London, Dept. Physics and Astronomy
- London
- UK
| | - R. Patel
- University College London, Dept. Physics and Astronomy
- London
- UK
| | - A. Taylor
- University College London, Dept. Physics and Astronomy
- London
- UK
| | - N. T. Skipper
- University College London, Dept. Physics and Astronomy
- London
- UK
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Hammond OS, Bowron DT, Jackson AJ, Arnold T, Sanchez-Fernandez A, Tsapatsaris N, Garcia Sakai V, Edler KJ. Resilience of Malic Acid Natural Deep Eutectic Solvent Nanostructure to Solidification and Hydration. J Phys Chem B 2017; 121:7473-7483. [DOI: 10.1021/acs.jpcb.7b05454] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Oliver S. Hammond
- Centre
for Sustainable Chemical Technologies, University of Bath, Claverton Down, Bath BA2
7AY, U.K
- Department
of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K
| | - Daniel T. Bowron
- ISIS
Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot OX11 0QX, U.K
| | - Andrew J. Jackson
- European Spallation
Source, Box 176, 221 00 Lund, Sweden
- Division
of Physical Chemistry, Department of Chemistry, Lund University, Box
124, 221 00 Lund, Sweden
| | - Thomas Arnold
- Diamond
Light Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot OX11 0QX, U.K
| | | | | | - Victoria Garcia Sakai
- ISIS
Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot OX11 0QX, U.K
| | - Karen J. Edler
- Centre
for Sustainable Chemical Technologies, University of Bath, Claverton Down, Bath BA2
7AY, U.K
- Department
of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K
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45
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Steinke N, Genina A, Lorenz CD, McLain SE. Salt Interactions in Solution Prevent Direct Association of Urea with a Peptide Backbone. J Phys Chem B 2017; 121:1866-1876. [DOI: 10.1021/acs.jpcb.6b12542] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Nicola Steinke
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, U.K
| | - Anna Genina
- Department of Physics, King’s College London, London SE1 9NH, U.K
| | | | - Sylvia E. McLain
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, U.K
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46
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Playford HY, Tucker MG, Bull CL. Neutron total scattering of crystalline materials in the gigapascal regime. J Appl Crystallogr 2017. [DOI: 10.1107/s1600576716018173] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Neutron total scattering of disordered crystalline materials provides direct experimental access to the local (short-range) structure. The ways in which this local structure agrees (or disagrees) with the long-range crystal structure can provide important insight into structure–property relationships. High-pressure neutron diffraction using a Paris–Edinburgh (P–E) pressure cell allows experimenters to explore the ways in which materials are affected by pressure, can reveal new synthetic routes to novel functional materials and has important applications in many areas, including geology, engineering and planetary science. However, the combination of these two experimental techniques poses unique challenges for both data collection and analysis. In this paper it is shown that, with only minor modifications to the standard P–E press setup, high-quality total scattering data can be obtained from crystalline materials in the gigapascal pressure regime on the PEARL diffractometer at ISIS. The quality of the data is assessed through the calculation of coordination numbers and the use of reverse Monte Carlo refinements. The time required to collect data of sufficient quality for detailed analysis is assessed and is found to be of the order of 8 h for a quartz sample. Finally, data from the perovskite LaCo0.35Mn0.65O3 are presented and reveal that PEARL total scattering data offer the potential of extracting local structural information from complex materials at high pressure.
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47
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The Structure of Water and Aqueous Systems. ACTA ACUST UNITED AC 2017. [DOI: 10.1016/b978-0-12-805324-9.00003-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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48
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Silva-Santisteban A, Steinke N, Johnston AJ, Ruiz GN, Carlos Pardo L, McLain SE. On the structure of prilocaine in aqueous and amphiphilic solutions. Phys Chem Chem Phys 2017; 19:12665-12673. [DOI: 10.1039/c7cp01723e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The solvation of prilocaine has been investigated in pure water and in amphiphilic solutions using a combination of neutron diffraction and simulations.
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Affiliation(s)
- Alvaro Silva-Santisteban
- Department of Biochemistry
- University of Oxford
- Oxford OX1 3QU
- UK
- Departament de Física i Enginyeria Nuclear & Barcelona Research Center in Multiscale Science and Engineering
| | - Nicola Steinke
- Department of Biochemistry
- University of Oxford
- Oxford OX1 3QU
- UK
| | | | - Guadalupe N. Ruiz
- Departament de Física i Enginyeria Nuclear & Barcelona Research Center in Multiscale Science and Engineering
- Universitat Politècnica de Catalunya
- 08019 Barcelona
- Spain
| | - Luis Carlos Pardo
- Departament de Física i Enginyeria Nuclear & Barcelona Research Center in Multiscale Science and Engineering
- Universitat Politècnica de Catalunya
- 08019 Barcelona
- Spain
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49
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Lenton S, Walsh DL, Rhys NH, Soper AK, Dougan L. Structural evidence for solvent-stabilisation by aspartic acid as a mechanism for halophilic protein stability in high salt concentrations. Phys Chem Chem Phys 2016; 18:18054-62. [PMID: 27327567 DOI: 10.1039/c6cp02684b] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Halophilic organisms have adapted to survive in high salt environments, where mesophilic organisms would perish. One of the biggest challenges faced by halophilic proteins is the ability to maintain both the structure and function at molar concentrations of salt. A distinct adaptation of halophilic proteins, compared to mesophilic homologues, is the abundance of aspartic acid on the protein surface. Mutagenesis and crystallographic studies of halophilic proteins suggest an important role for solvent interactions with the surface aspartic acid residues. This interaction, between the regions of the acidic protein surface and the solvent, is thought to maintain a hydration layer around the protein at molar salt concentrations thereby allowing halophilic proteins to retain their functional state. Here we present neutron diffraction data of the monomeric zwitterionic form of aspartic acid solutions at physiological pH in 0.25 M and 2.5 M concentration of potassium chloride, to mimic mesophilic and halophilic-like environmental conditions. We have used isotopic substitution in combination with empirical potential structure refinement to extract atomic-scale information from the data. Our study provides structural insights that support the hypothesis that carboxyl groups on acidic residues bind water more tightly under high salt conditions, in support of the residue-ion interaction model of halophilic protein stabilisation. Furthermore our data show that in the presence of high salt the self-association between the zwitterionic form of aspartic acid molecules is reduced, suggesting a possible mechanism through which protein aggregation is prevented.
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Affiliation(s)
- Samuel Lenton
- School of Physics and Astronomy, University of Leeds, Leeds, UK.
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50
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Steinke N, Gillams RJ, Pardo LC, Lorenz CD, McLain SE. Atomic scale insights into urea–peptide interactions in solution. Phys Chem Chem Phys 2016; 18:3862-70. [DOI: 10.1039/c5cp06646h] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Investigations on the β-turn forming peptide, GPG, suggest that urea denatures proteins by replacing water molecules and subsequently weakening the peptide bonds as a possible mechanism of protein denaturation by urea.
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Affiliation(s)
- Nicola Steinke
- Department of Biochemistry
- University of Oxford
- Oxford OX1 3QU
- UK
| | | | - Luis Carlos Pardo
- Departament de Física i Enginyeria Nuclear
- Escola Tècnica Superior d'Enginyeria Industrial de Barcelona (ETSEIB)
- Universitat Politècnica de Catalunya
- 08028 Barcelona
- Catalonia, Spain
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