1
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Leoni F, Martelli F, Russo J. Correlating Ultrastability with Fragility and Surface Mobility in Vapor Deposited Tetrahedral Glasses. J Phys Chem Lett 2024; 15:8444-8450. [PMID: 39121353 DOI: 10.1021/acs.jpclett.4c01633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/11/2024]
Abstract
Several experiments on molecular and metallic glasses have shown that the ability of vapor deposition to produce ultrastable glasses is correlated to their structural and thermodynamic properties. Here we investigate the vapor deposition of a class of tetrahedral materials (including silicon and water) via molecular dynamics simulations of the generalized Stillinger-Weber potential. By changing a single parameter that controls the local tetrahedrality, we show that the emergence of ultrastable behavior is correlated with an increase in the fragility of the model. At the same time, while the mobility of the surface compared to the bulk shows only slight changes at low temperature, with increasing the tetrahedrality, it displays a significant enhancement toward the glass transition temperature. Our results point toward a strong connection between bulk dynamics, surface dynamics, and glass-ultrastability ability in this class of materials.
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Affiliation(s)
- Fabio Leoni
- Dipartimento di Fisica, Università degli Studi di Roma La Sapienza, Piazzale Aldo Moro 5, Rome 00185, Italy
| | | | - John Russo
- Dipartimento di Fisica, Università degli Studi di Roma La Sapienza, Piazzale Aldo Moro 5, Rome 00185, Italy
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2
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Richert R. Dielectric Study of n-Propanol during Physical Vapor Deposition: No Surface Mobility and No Kinetic Stability. J Phys Chem B 2024; 128:5528-5533. [PMID: 38781977 DOI: 10.1021/acs.jpcb.4c01904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
Dielectric relaxation experiments have been performed on n-propanol (NPOH) films during physical vapor deposition at temperatures above and below its glass transition, Tg = 97 K. The results for NPOH are compared with those of analogous experiments on methyl-m-toluate (MMT) and 2-methyltetrahydrofuran (MTHF), with all three deposited at the same reduced temperature, 0.82Tg. While MMT and MTHF display clear signs of a highly mobile surface layer, no such feature is observed for NPOH. The existence of this in situ observed mobile surface layer correlates perfectly with the material's ability to form kinetically stable glasses, as NPOH differs from MMT and MTHF by not displaying kinetic stability.
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Affiliation(s)
- R Richert
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States
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3
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Wolf SE, Fulco S, Zhang A, Zhao H, Walsh PJ, Turner KT, Fakhraai Z. Role of Molecular Layering in the Enhanced Mechanical Properties of Stable Glasses. J Phys Chem Lett 2022; 13:3360-3368. [PMID: 35403428 DOI: 10.1021/acs.jpclett.2c00232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The density, degree of molecular orientation, and molecular layering of vapor-deposited stable glasses (SGs) vary with substrate temperature (Tdep) below the glass-transition temperature (Tg). Density and orientation have been suggested to be factors influencing the mechanical properties of SGs. We perform nanoindentation on two molecules which differ by only a single substituent, allowing one molecule to adopt an in-plane orientation at low Tdep. The reduced elastic modulus and hardness of both molecules show similar Tdep dependences, with enhancements of 15-20% in reduced modulus and 30-45% in hardness at Tdep ≈ 0.8Tg, where the density of vapor-deposited films is enhanced by ∼1.4% compared to that of the liquid-quenched glass. At Tdep < 0.8Tg, one of the molecules produces highly unstable glasses with in-plane orientation. However, both systems show enhanced mechanics. Both the modulus and hardness correlate with the degree of layering, which is similar in both systems despite their variable stability. We suggest that nanoindentation performed normal to the film's surface is influenced by the tighter packing of the molecules in this direction.
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4
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Li Y, Annamareddy A, Morgan D, Yu Z, Wang B, Cao C, Perepezko JH, Ediger MD, Voyles PM, Yu L. Surface Diffusion Is Controlled by Bulk Fragility across All Glass Types. PHYSICAL REVIEW LETTERS 2022; 128:075501. [PMID: 35244425 DOI: 10.1103/physrevlett.128.075501] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 01/07/2022] [Indexed: 06/14/2023]
Abstract
Surface diffusion is vastly faster than bulk diffusion in some glasses, but only moderately enhanced in others. We show that this variation is closely linked to bulk fragility, a common measure of how quickly dynamics is excited when a glass is heated to become a liquid. In fragile molecular glasses, surface diffusion can be a factor of 10^{8} faster than bulk diffusion at the glass transition temperature, while in the strong system SiO_{2}, the enhancement is a factor of 10. Between these two extremes lie systems of intermediate fragility, including metallic glasses and amorphous selenium and silicon. This indicates that stronger liquids have greater resistance to dynamic excitation from bulk to surface and enables prediction of surface diffusion, surface crystallization, and formation of stable glasses by vapor deposition.
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Affiliation(s)
- Yuhui Li
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
| | - Ajay Annamareddy
- Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Dane Morgan
- Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Zheng Yu
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Bu Wang
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Chengrong Cao
- Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - John H Perepezko
- Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - M D Ediger
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Paul M Voyles
- Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Lian Yu
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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5
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Wolf SE, Liu T, Govind S, Zhao H, Huang G, Zhang A, Wu Y, Chin J, Cheng K, Salami-Ranjbaran E, Gao F, Gao G, Jin Y, Pu Y, Toledo TG, Ablajan K, Walsh PJ, Fakhraai Z. Design of a homologous series of molecular glassformers. J Chem Phys 2021; 155:224503. [PMID: 34911316 DOI: 10.1063/5.0066410] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We design and synthesize a set of homologous organic molecules by taking advantage of facile and tailorable Suzuki cross coupling reactions to produce triarylbenzene derivatives. By adjusting the number and the arrangement of conjugated rings, the identity of heteroatoms, lengths of fluorinated alkyl chains, and other interaction parameters, we create a library of glassformers with a wide range of properties. Measurements of the glass transition temperature (Tg) show a power-law relationship between Tg and molecular weight (MW), with of the molecules, with an exponent of 0.3 ± 0.1, for Tg values spanning a range of 300-450 K. The trends in indices of refraction and expansion coefficients indicate a general increase in the glass density with MW, consistent with the trends observed in Tg variations. A notable exception to these trends was observed with the addition of alkyl and fluorinated alkyl groups, which significantly reduced Tg and increased the dynamical fragility (which is otherwise insensitive to MW). This is an indication of reduced density and increased packing frustrations in these systems, which is also corroborated by the observations of the decreasing index of refraction with increasing length of these groups. These data were used to launch a new database for glassforming materials, glass.apps.sas.upenn.edu.
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Affiliation(s)
- Sarah E Wolf
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Tianyi Liu
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Shivajee Govind
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Haoqiang Zhao
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Georgia Huang
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Aixi Zhang
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Yu Wu
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Jocelyn Chin
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Kevin Cheng
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | | | - Feng Gao
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Gui Gao
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Yi Jin
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Youge Pu
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Thiago Gomes Toledo
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Keyume Ablajan
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Patrick J Walsh
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Zahra Fakhraai
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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6
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Tournier RF, Ojovan MI. Prediction of Second Melting Temperatures Already Observed in Pure Elements by Molecular Dynamics Simulations. MATERIALS 2021; 14:ma14216509. [PMID: 34772033 PMCID: PMC8585396 DOI: 10.3390/ma14216509] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/19/2021] [Accepted: 10/26/2021] [Indexed: 12/01/2022]
Abstract
A second melting temperature occurs at a temperature Tn+ higher than Tm in glass-forming melts after heating them from their glassy state. The melting entropy is reduced or increased depending on the thermal history and on the presence of antibonds or bonds up to Tn+. Recent MD simulations show full melting at Tn+ = 1.119Tm for Zr, 1.126Tm for Ag, 1.219Tm for Fe and 1.354Tm for Cu. The non-classical homogeneous nucleation model applied to liquid elements is based on the increase of the Lindemann coefficient with the heating rate. The glass transition at Tg and the nucleation temperatures TnG of glacial phases are successfully predicted below and above Tm. The glass transition temperature Tg increases with the heating rate up to Tn+. Melting and crystallization of glacial phases occur with entropy and enthalpy reductions. A universal law relating Tn+ and TnG around Tm shows that TnG cannot be higher than 1.293Tm for Tn+= 1.47Tm. The enthalpies and entropies of glacial phases have singular values, corresponding to the increase of percolation thresholds with Tg and TnG above the Scher and Zallen invariant at various heating and cooling rates. The G-phases are metastable up to Tn+ because the antibonds are broken by homogeneous nucleation of bonds.
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Affiliation(s)
- Robert F. Tournier
- UPR 3228 Centre National de la Recherche Scientifique, Laboratoire National des Champs Magnétiques Intenses, European Magnetic Field Laboratory, Institut National des Sciences Appliquées de Toulouse, Université Grenoble Alpes, F-31400 Toulouse, France
- Correspondence:
| | - Michael I. Ojovan
- Department of Materials, Imperial College London, London SW7 2AZ, UK;
- Department of Radiochemistry, Moscow State University, 119991 Moscow, Russia
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7
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Tourlakis GM, Adamopoulos SAT, Gavra IK, Milpanis AA, Tsagri LF, Pachygianni ASG, Chatzikokolis SS, Tsekouras AA. Sign flipping of spontaneous polarization in vapour-deposited films of small polar organic molecules. Phys Chem Chem Phys 2021; 23:14352-14362. [PMID: 34169950 DOI: 10.1039/d1cp01584b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Films of polar molecules vapour-deposited on sufficiently cold substrates are not only amorphous, but also exhibit charge polarization across their thickness. This is an effect known for 50 years, but it is very poorly understood and no mechanism exists in the literature that can explain and predict it. We investigated this bulk effect for 18 small organic molecules as a function of substrate temperature (30-130 K). We found that, as a rule, alcohol films have the negative end on the vacuum side at all temperatures. Alkyl acetates and toluene showed positive voltages which reached a maximum around the middle of the temperature range investigated. Tetrahydrofuran showed positive voltages which dropped with increasing deposition temperature. Diethyl ether, acetone, propanal, and butanal showed positive film voltages at low temperatures, negative at intermediate temperatures and again positive voltages at higher temperatures. In all cases, film voltages were monitored during heating leading to film evaporation. Film voltages were irreversibly eliminated before film elimination, but voltage profiles during temperature ramps differed vastly depending on compound and deposition temperature. In general, there was a gradual voltage reduction, but propanal, butanal, and diethyl ether showed a change in voltage sign during temperature ramp in films deposited at low temperatures. All these data expand substantially the experimental information regarding spontaneous polarization in vapour-deposited films, but still require complementary measurements as well as numerical simulations for a detailed explanation of the phenomenon.
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Affiliation(s)
- Georgios M Tourlakis
- Physical Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, GR-15784, Greece.
| | - Sotirios Alexandros T Adamopoulos
- Physical Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, GR-15784, Greece.
| | - Irini K Gavra
- Physical Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, GR-15784, Greece.
| | - Alexandros A Milpanis
- Physical Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, GR-15784, Greece.
| | - Liveria F Tsagri
- Physical Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, GR-15784, Greece.
| | - Aikaterini Sofia G Pachygianni
- Physical Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, GR-15784, Greece.
| | - Stylianos S Chatzikokolis
- Physical Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, GR-15784, Greece.
| | - Athanassios A Tsekouras
- Physical Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, GR-15784, Greece.
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8
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Castel A, Gutfreund P, Cabane B, Rharbi Y. Stability of Fluid Ultrathin Polymer Films in Contact with Solvent-Loaded Gels for Cultural Heritage. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:12607-12619. [PMID: 33044083 DOI: 10.1021/acs.langmuir.0c02162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The removal of ultrathin amorphous polymer films in contact with an aqueous gelled solution containing small amounts of good solvent is addressed by means of specular and off-specular neutron reflectometry. The distribution of heavy water and benzyl alcohol is revealed inside Laropal A81, often employed as a protective varnish layer for Culture Heritage in the restoration of easel paintings. The swelling kinetics, interface roughness, and film morphologies were recorded as a function of temperature and increasing benzyl alcohol concentration in the dispersion of Pemulen TR-2, a hydrophobically modified acrylic acid copolymer. The addition of small amounts of good solvent results in the appearance of water-filled cavities inside the varnish, which grow with time. It is shown that while increasing the solvent concentration greatly enhances the hole growth kinetics, an increase in temperature above the glass transition temperature does not have such a big effect on the kinetics.
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Affiliation(s)
- Amélie Castel
- Large Scale Structures Group, Institut Laue-Langevin, Grenoble 38000, France
- Laboratoire de Rhéologie et Procédés, Grenoble 38000, France
| | - Philipp Gutfreund
- Large Scale Structures Group, Institut Laue-Langevin, Grenoble 38000, France
| | | | - Yahya Rharbi
- Laboratoire de Rhéologie et Procédés, Grenoble 38000, France
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9
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Beasley MS, Kasting BJ, Tracy ME, Guiseppi-Elie A, Richert R, Ediger MD. Physical vapor deposition of a polyamorphic system: Triphenyl phosphite. J Chem Phys 2020; 153:124511. [PMID: 33003706 DOI: 10.1063/5.0019872] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
In situ AC nanocalorimetry and dielectric spectroscopy were used to analyze films of vapor-deposited triphenyl phosphite. The goal of this work was to investigate the properties of vapor-deposited glasses of this known polyamorphic system and to determine which liquid is formed when the glass is heated. We find that triphenyl phosphite forms a kinetically stable glass when prepared at substrate temperatures of 0.75-0.95Tg, where Tg is the glass transition temperature. Regardless of the substrate temperature utilized during deposition of triphenyl phosphite, heating a vapor-deposited glass always forms the ordinary supercooled liquid (liquid 1). The identity of liquid 1 was confirmed by both the calorimetric signal and the shape and position of the dielectric spectra. For the purposes of comparison, the glacial phase of triphenyl phosphite (liquid 2) was prepared by the conventional method of annealing liquid 1. We speculate that these new results and previous work on vapor deposition of other polyamorphic systems can be explained by the free surface structure being similar to one polyamorph even in a temperature regime where the other polyamorph is more thermodynamically stable in the bulk.
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Affiliation(s)
- M S Beasley
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - B J Kasting
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - M E Tracy
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - A Guiseppi-Elie
- Department of Biomedical Engineering, Texas A&M University, College Station, Texas 77843, USA
| | - R Richert
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287, USA
| | - M D Ediger
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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10
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Khomenko D, Scalliet C, Berthier L, Reichman DR, Zamponi F. Depletion of Two-Level Systems in Ultrastable Computer-Generated Glasses. PHYSICAL REVIEW LETTERS 2020; 124:225901. [PMID: 32567893 DOI: 10.1103/physrevlett.124.225901] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 04/28/2020] [Indexed: 06/11/2023]
Abstract
Amorphous solids exhibit quasiuniversal low temperature anomalies whose origin has been ascribed to localized tunneling defects. Using an advanced Monte Carlo procedure, we create in silico glasses spanning from hyperquenched to ultrastable glasses. Using a multidimensional path-finding protocol, we locate tunneling defects with energy splittings smaller than k_{B}T_{Q}, with T_{Q} the temperature below which quantum effects are relevant (T_{Q}≈1 K in most experiments). We find that as the stability of a glass increases, its energy landscape as well as the manner in which it is probed tend to deplete the density of tunneling defects, as observed in recent experiments. We explore the real-space nature of tunneling defects, and find that they are mostly localized to a few atoms, but are occasionally dramatically delocalized.
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Affiliation(s)
- Dmytro Khomenko
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, 75005 Paris, France
- Department of Chemistry, Columbia University, New York, New York 10027, USA
| | - Camille Scalliet
- DAMTP, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA, United Kingdom
| | - Ludovic Berthier
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
- Laboratoire Charles Coulomb (L2C), Université de Montpellier, CNRS, 34095 Montpellier, France
| | - David R Reichman
- Department of Chemistry, Columbia University, New York, New York 10027, USA
| | - Francesco Zamponi
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, 75005 Paris, France
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11
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Castel A, Gutfreund P, Cabane B, Rharbi Y. Swelling, dewetting and breakup in thin polymer films for cultural heritage. SOFT MATTER 2020; 16:1485-1497. [PMID: 31930258 DOI: 10.1039/c9sm01976f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The removal of ultrathin amorphous polymer films in contact with nonsolvent/solvent binary mixtures is addressed by means of neutron reflectometry and atomic force microscopy. The high resolution of neutron scattering makes it possible to resolve the distribution profiles of heavy water and benzyl alcohol inside Laropal®A81, often employed as a protective varnish layer for Culture Heritage in restoration of easel paintings. The swelling kinetics and distribution profiles were recorded as a function of time and increasing benzyl alcohol concentration in water. The varnish film swells by penetration of the good solvent. At higher concentrations water-filled cavities appear inside the varnish and grow with time. Contrary to homogeneous dissolution dewetting is observed at late stages of exposure to the liquid which leads to the Breakup of the film. The high resolution measurements are compared to bulk behaviour characterized by the ternary phase diagram and the Flory-Huggins interaction parameters are calculated and used to predict the swelling and solvent partition in the films. Distinct differences of the thin film to bulk behaviour are found. The expectations made previously for the behaviour of solvent/non-solvent mixtures on the removal of thin layers in the restoration of easel paintings should be revised in view of surface interactions.
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12
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Riechers B, Guiseppi-Elie A, Ediger MD, Richert R. Dielectric properties of vapor-deposited propylbenzenes. J Chem Phys 2019; 151:174503. [DOI: 10.1063/1.5125138] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Birte Riechers
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287-1604, USA
| | - A. Guiseppi-Elie
- Department of Biomedical Engineering, The Dwight Look College of Engineering, Texas A&M University, College Station, Texas 77843, USA
| | - M. D. Ediger
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Ranko Richert
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287-1604, USA
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13
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Pilidi AN, Gavra IK, Tsekouras AA. Spontaneous Polarization of Cryo-Deposited Films for Five Normal Saturated Monohydroxy Alcohols, CnH2n+1OH, n = 1–5. J Phys Chem B 2019; 123:8505-8511. [DOI: 10.1021/acs.jpcb.9b04978] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Alexandra N. Pilidi
- Physical Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos GR-15771, Greece
| | - Irini K. Gavra
- Physical Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos GR-15771, Greece
| | - Athanassios A. Tsekouras
- Physical Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos GR-15771, Greece
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14
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Beasley MS, Bishop C, Kasting BJ, Ediger MD. Vapor-Deposited Ethylbenzene Glasses Approach "Ideal Glass" Density. J Phys Chem Lett 2019; 10:4069-4075. [PMID: 31269793 DOI: 10.1021/acs.jpclett.9b01508] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Spectroscopic ellipsometry was used to characterize vapor-deposited glasses of ethylbenzene (Tg = 115.7 K). For this system, previous calorimetric experiments have established that a transition to the ideal glass state is expected to occur near 101 K (the Kauzmann temperature, TK) if the low-temperature supercooled liquid has the properties expected based upon extrapolation from above Tg. Ethylbenzene glasses were vapor-deposited at substrate temperatures between 100 (∼0.86 Tg) and 116 K (∼Tg), using deposition rates of 0.02-2.1 nm/s. Down to 103 K, glasses prepared in the limit of low deposition rate have densities consistent with the extrapolated supercooled liquid. The highest density glass is within 0.15% of the density expected for the ideal glass. These results support the hypothesis that the extrapolated properties of supercooled ethylbenzene are correct to within just a few Kelvin of TK, consistent with the existence of a phase transition to an ideal glass state at TK.
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Affiliation(s)
- M S Beasley
- Department of Chemistry , University of Wisconsin-Madison , Madison , Wisconsin 53706 , United States
| | - C Bishop
- Department of Chemistry , University of Wisconsin-Madison , Madison , Wisconsin 53706 , United States
| | - B J Kasting
- Department of Chemistry , University of Wisconsin-Madison , Madison , Wisconsin 53706 , United States
| | - M D Ediger
- Department of Chemistry , University of Wisconsin-Madison , Madison , Wisconsin 53706 , United States
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15
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Impact of jamming criticality on low-temperature anomalies in structural glasses. Proc Natl Acad Sci U S A 2019; 116:13768-13773. [PMID: 31235596 DOI: 10.1073/pnas.1820360116] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We present a mechanism for the anomalous behavior of the specific heat in low-temperature amorphous solids. The analytic solution of a mean-field model belonging to the same universality class as high-dimensional glasses, the spherical perceptron, suggests that there exists a cross-over temperature above which the specific heat scales linearly with temperature, while below it, a cubic scaling is displayed. This relies on two crucial features of the phase diagram: (i) the marginal stability of the free-energy landscape, which induces a gapless phase responsible for the emergence of a power-law scaling; and (ii) the vicinity of the classical jamming critical point, as the cross-over temperature gets lowered when approaching it. This scenario arises from a direct study of the thermodynamics of the system in the quantum regime, where we show that, contrary to crystals, the Debye approximation does not hold.
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16
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Samanta S, Huang G, Gao G, Zhang Y, Zhang A, Wolf S, Woods CN, Jin Y, Walsh PJ, Fakhraai Z. Exploring the Importance of Surface Diffusion in Stability of Vapor-Deposited Organic Glasses. J Phys Chem B 2019; 123:4108-4117. [PMID: 30998844 DOI: 10.1021/acs.jpcb.9b01012] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Stable glasses are formed during physical vapor deposition (PVD), through the surface-mediated equilibration process. Understanding surface relaxation dynamics is important in understanding the details of this process. Direct measurements of the surface relaxation times in molecular glass systems are challenging. As such, surface diffusion measurements have been used in the past as a proxy for the surface relaxation process. In this study, we show that the absence of enhanced surface diffusion is not a reliable predictor of reduced ability to produce stable glasses. To demonstrate, we have prepared stable glasses (SGs) from two structurally similar organic molecules, 1,3-bis(1-naphthyl)-5-(2-naphthyl)benzene (TNB) and 9-(3,5-di(naphthalen-1-yl)phenyl)anthracene (α,α-A), with similar density increase and improved kinetic stability as compared to their liquid-quenched (LQ) counterparts. The surface diffusion values of these glasses were measured both in the LQ and SG states below their glass transition temperatures ( Tgs) using gold nanorod probes. While TNB shows enhanced surface diffusion in both SG and LQ states, no significant surface Tg diffusion is observed on the surface of α,α-A within our experimental time scales. However, isothermal dewetting experiments on ultrathin films of both molecules below Tg indicate the existence of enhanced dynamics in ultrathin films for both molecules, indirectly showing the existence of an enhanced mobile surface layer. Both films produce stable glasses, which is another indication for the existence of the mobile surface layer. Our results suggest that lateral surface diffusion may not be a good proxy for enhanced surface relaxation dynamics required to produce stable glasses, and thus, other types of measurements to directly probe the surface relaxation times may be necessary.
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Affiliation(s)
- Subarna Samanta
- Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104-6323 , United States
| | - Georgia Huang
- Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104-6323 , United States
| | - Gui Gao
- Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104-6323 , United States
| | - Yue Zhang
- Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104-6323 , United States
| | - Aixi Zhang
- Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104-6323 , United States
| | - Sarah Wolf
- Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104-6323 , United States
| | - Connor N Woods
- Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104-6323 , United States
| | - Yi Jin
- Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104-6323 , United States
| | - Patrick J Walsh
- Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104-6323 , United States
| | - Zahra Fakhraai
- Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104-6323 , United States
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17
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Moore AR, Huang G, Wolf S, Walsh PJ, Fakhraai Z, Riggleman RA. Effects of microstructure formation on the stability of vapor-deposited glasses. Proc Natl Acad Sci U S A 2019; 116:5937-5942. [PMID: 30867283 PMCID: PMC6442635 DOI: 10.1073/pnas.1821761116] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Glasses formed by physical vapor deposition (PVD) are an interesting new class of materials, exhibiting properties thought to be equivalent to those of glasses aged for thousands of years. Exerting control over the structure and properties of PVD glasses formed with different types of glass-forming molecules is now an emerging challenge. In this work, we study coarse-grained models of organic glass formers containing fluorocarbon tails of increasing length, corresponding to an increased tendency to form microstructures. We use simulated PVD to examine how the presence of the microphase-separated domains in the supercooled liquid influences the ability to form stable glasses. This model suggests that increasing molecule tail length results in decreased thermodynamic stability of the molecules in PVD films. The reduced stability is further linked to the reduced ability of these molecules to equilibrate at the free surface during PVD. We find that, as the tail length is increased, the relaxation times near the surface of the supercooled equilibrium liquid films of these molecules are slowed and become essentially bulk-like, due to the segregation of the fluorocarbon tails to the free surface. Surface diffusion is also markedly reduced due to clustering of the molecules at the surface. Based on these results, we propose a trapping mechanism where tails are unable to move between local phase-separated domains on the relevant deposition time scales.
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Affiliation(s)
- Alex R Moore
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, PA 19104
| | - Georgia Huang
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104
| | - Sarah Wolf
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104
| | - Patrick J Walsh
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104
| | - Zahra Fakhraai
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, PA 19104
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104
| | - Robert A Riggleman
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, PA 19104;
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18
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Cubeta US, Sadtchenko V. Glass softening kinetics in the limit of high heating rates. J Chem Phys 2019; 150:094508. [DOI: 10.1063/1.5046304] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Ulyana S. Cubeta
- Chemistry Department, The George Washington University, Washington, District of Columbia 20052, USA
| | - Vlad Sadtchenko
- Chemistry Department, The George Washington University, Washington, District of Columbia 20052, USA
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19
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Chen Y, Chen Z, Tylinski M, Ediger MD, Yu L. Effect of molecular size and hydrogen bonding on three surface-facilitated processes in molecular glasses: Surface diffusion, surface crystal growth, and formation of stable glasses by vapor deposition. J Chem Phys 2019; 150:024502. [DOI: 10.1063/1.5079441] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Yinshan Chen
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
| | - Zhenxuan Chen
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
| | - Michael Tylinski
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - M. D. Ediger
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Lian Yu
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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20
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Vila-Costa A, Ràfols-Ribé J, Gonzalez-Silveira M, Lopeandía A, Tamarit JL, Rodríguez-Viejo J. Multiple glass transitions in vapor-deposited orientational glasses of the most fragile plastic crystal Freon 113. Phys Chem Chem Phys 2019; 21:10436-10441. [DOI: 10.1039/c9cp00976k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Stable glass formation for both structural glass and as-deposited glassy crystal at deposition temperatures below Tg.
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Affiliation(s)
- A. Vila-Costa
- Grup de Nanomaterials i Microsistemes
- Departament de Física
- Universitat Autònoma de Barcelona
- 08193 Bellaterra
- Spain
| | - J. Ràfols-Ribé
- Grup de Nanomaterials i Microsistemes
- Departament de Física
- Universitat Autònoma de Barcelona
- 08193 Bellaterra
- Spain
| | - M. Gonzalez-Silveira
- Grup de Nanomaterials i Microsistemes
- Departament de Física
- Universitat Autònoma de Barcelona
- 08193 Bellaterra
- Spain
| | - A. Lopeandía
- Grup de Nanomaterials i Microsistemes
- Departament de Física
- Universitat Autònoma de Barcelona
- 08193 Bellaterra
- Spain
| | - J. Ll. Tamarit
- Grup de Caracterització de Materials
- Departament de Física and Barcelona Research Center in Multiscale Science and Engineering
- Universitat Politècnica de Catalunya
- EEBE
- 08019 Barcelona
| | - J. Rodríguez-Viejo
- Grup de Nanomaterials i Microsistemes
- Departament de Física
- Universitat Autònoma de Barcelona
- 08193 Bellaterra
- Spain
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21
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Saini MK, Guo Y, Wu T, Ngai KL, Wang LM. Deviations of dynamic parameters characterizing enthalpic and dielectric relaxations in glass forming alkyl phosphates. J Chem Phys 2018; 149:204505. [PMID: 30501246 DOI: 10.1063/1.5051570] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In our recent study [T. Wu et al., J. Chem. Phys. 147, 134501 (2017)], an alkyl phosphate glass former was studied and it suggested that the enthalpy relaxation involving the motions of all parts of the molecule is global, while the dielectric relaxation detects the local rotation of the polar core. In this work, we study a series of trialkyl phosphates using calorimetric and dielectric measurements over a wide temperature range. The results indicate a departure of the dielectric fragility indexes from the enthalpic ones as the length of the branch chain increases in the trialkyl phosphates. The Kirkwood correlation factor (g k ) is found to coincide at ∼0.6 at glass transition temperature (T g ) from triethyl phosphate to tributyl phosphate, indicating a similar structural alignment. The enthalpic relaxation serving as the more fundamental relaxation relevant to the structural relaxation is confirmed. Strikingly, we observed the relation of T g to the chain length in alkyl phosphates, revealing a minimum T g behavior, and its explanation assists in the understanding of the glass transition in relation to the structure of the glass-formers.
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Affiliation(s)
- Manoj K Saini
- State Key Lab of Metastable Materials Science and Technology, College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei 066004, China
| | - Yuxing Guo
- State Key Lab of Metastable Materials Science and Technology, College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei 066004, China
| | - Tao Wu
- State Key Lab of Metastable Materials Science and Technology, College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei 066004, China
| | - K L Ngai
- State Key Lab of Metastable Materials Science and Technology, College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei 066004, China
| | - Li-Min Wang
- State Key Lab of Metastable Materials Science and Technology, College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei 066004, China
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22
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Chua YZ, Young-Gonzales AR, Richert R, Ediger MD, Schick C. Dynamics of supercooled liquid and plastic crystalline ethanol: Dielectric relaxation and AC nanocalorimetry distinguish structural α- and Debye relaxation processes. J Chem Phys 2018; 147:014502. [PMID: 28688431 DOI: 10.1063/1.4991006] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Physical vapor deposition has been used to prepare glasses of ethanol. Upon heating, the glasses transformed into the supercooled liquid phase and then crystallized into the plastic crystal phase. The dynamic glass transition of the supercooled liquid is successfully measured by AC nanocalorimetry, and preliminary results for the plastic crystal are obtained. The frequency dependences of these dynamic glass transitions observed by AC nanocalorimetry are in disagreement with conclusions from previously published dielectric spectra of ethanol. Existing dielectric loss spectra have been carefully re-evaluated considering a Debye peak, which is a typical feature in the dielectric loss spectra of monohydroxy alcohols. The re-evaluated dielectric fits reveal a prominent dielectric Debye peak, a smaller and asymmetrically broadened peak, which is identified as the signature of the structural α-relaxation and a Johari-Goldstein secondary relaxation process. This new assignment of the dielectric processes is supported by the observation that the AC nanocalorimetry dynamic glass transition temperature, Tα, coincides with the dielectric structural α-relaxation process rather than the Debye process. The combined results from dielectric spectroscopy and AC nanocalorimetry on the plastic crystal of ethanol suggest the occurrence of a Debye process also in the plastic crystal phase.
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Affiliation(s)
- Y Z Chua
- Institute of Physics, University of Rostock, Albert-Einstein-Str. 23-24, 18051 Rostock, Germany and Competence Centre CALOR, Faculty of Interdisciplinary Research, University of Rostock, Albert-Einstein-Str. 25, 18051 Rostock, Germany
| | - A R Young-Gonzales
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287-1604, USA
| | - R Richert
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287-1604, USA
| | - M D Ediger
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - C Schick
- Institute of Physics, University of Rostock, Albert-Einstein-Str. 23-24, 18051 Rostock, Germany and Competence Centre CALOR, Faculty of Interdisciplinary Research, University of Rostock, Albert-Einstein-Str. 25, 18051 Rostock, Germany
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23
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Beasley MS, Tylinski M, Chua YZ, Schick C, Ediger MD. Glasses of three alkyl phosphates show a range of kinetic stabilities when prepared by physical vapor deposition. J Chem Phys 2018; 148:174503. [DOI: 10.1063/1.5026505] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- M. S. Beasley
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - M. Tylinski
- Department of Chemistry, Widener University, Chester, Pennsylvania 19013, USA
| | - Y. Z. Chua
- Institute of Physics, University of Rostock, Albert-Einstein-Str. 23-24, 18051 Rostock, Germany and Competence Center CALOR, Faculty of Interdisciplinary Research, University of Rostock, Albert-Einstein-Str. 25, 18051 Rostock, Germany
| | - C. Schick
- Institute of Physics, University of Rostock, Albert-Einstein-Str. 23-24, 18051 Rostock, Germany and Competence Center CALOR, Faculty of Interdisciplinary Research, University of Rostock, Albert-Einstein-Str. 25, 18051 Rostock, Germany
| | - M. D. Ediger
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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24
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Affiliation(s)
- M. D. Ediger
- Department of Chemistry, University of Wisconsin-Madison,
1101 University Avenue, Madison, Wisconsin 53706, USA
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25
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Young-Gonzales AR, Guiseppi-Elie A, Ediger MD, Richert R. Modifying hydrogen-bonded structures by physical vapor deposition: 4-methyl-3-heptanol. J Chem Phys 2017; 147:194504. [PMID: 29166100 DOI: 10.1063/1.4999300] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
We prepared films of 4-methyl-3-heptanol by vapor depositing onto substrates held at temperatures between Tdep = 0.6Tg and Tg, where Tg is the glass transition temperature. Using deposition rates between 0.9 and 6.0 nm/s, we prepared films about 5 μm thick and measured the dielectric properties via an interdigitated electrode cell onto which films were deposited. Samples prepared at Tdep = Tg display the dielectric behavior of the ordinary supercooled liquid. Films deposited at lower deposition temperatures show a high dielectric loss upon heating toward Tg, which decreases by a factor of about 12 by annealing at Tg = 162 K. This change is consistent with either a drop of the Kirkwood correlation factor, gk, by a factor of about 10, or an increase in the dielectric relaxation times, both being indicative of changes toward ring-like hydrogen-bonded structure characteristic of the ordinary liquid. We rationalize the high dielectric relaxation amplitude in the vapor deposited glass by suggesting that depositions at low temperature provide insufficient time for molecules to form ring-like supramolecular structures for which dipole moments cancel. Surprisingly, above Tg of the ordinary liquid, these vapor deposited films fail to completely recover the dielectric properties of the liquid obtained by supercooling. Instead, the dielectric relaxation remains slower and its amplitude much higher than that of the equilibrium liquid state, indicative of a structure that differs from the equilibrium liquid up to at least Tg + 40 K.
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Affiliation(s)
- A R Young-Gonzales
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287-1604, USA
| | - A Guiseppi-Elie
- Department of Biomedical Engineering, The Dwight Look College of Engineering, Texas A&M University, College Station, Texas 77843, USA
| | - M D Ediger
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
| | - R Richert
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287-1604, USA
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26
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Chen Y, Zhu M, Laventure A, Lebel O, Ediger MD, Yu L. Influence of Hydrogen Bonding on the Surface Diffusion of Molecular Glasses: Comparison of Three Triazines. J Phys Chem B 2017. [PMID: 28651429 DOI: 10.1021/acs.jpcb.7b05333] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Surface grating decay measurements have been performed on three closely related molecular glasses to study the effect of intermolecular hydrogen bonds on surface diffusion. The three molecules are derivatives of bis(3,5-dimethyl-phenylamino)-1,3,5-triazine and differ only in the functional group R at the 2-position, with R being C2H5, OCH3, and NHCH3, and referred to as "Et", "OMe", and "NHMe", respectively. Of the three molecules, NHMe forms more extensive intermolecular hydrogen bonds than Et and OMe and was found to have slower surface diffusion. For Et and OMe, surface diffusion is so fast that it replaces viscous flow as the mechanism of surface grating decay as temperature is lowered. In contrast, no such transition was observed for NHMe under the same conditions, indicating significantly slower surface diffusion. This result is consistent with the previous finding that extensive intermolecular hydrogen bonds slow down surface diffusion in molecular glasses and is attributed to the persistence of hydrogen bonds even in the surface environment. This result is also consistent with the lower stability of the vapor-deposited glass of NHMe relative to those of Et and OMe and supports the view that surface mobility controls the stability of vapor-deposited glasses.
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Affiliation(s)
- Yinshan Chen
- School of Pharmacy, University of Wisconsin-Madison , Madison, Wisconsin 53705, United States
| | - Men Zhu
- Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Audrey Laventure
- Department of Chemistry and Chemical Engineering, Royal Military College of Canada , Kingston, Ontario K7K 7B4, Canada
| | - Olivier Lebel
- Department of Chemistry and Chemical Engineering, Royal Military College of Canada , Kingston, Ontario K7K 7B4, Canada
| | - M D Ediger
- Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Lian Yu
- School of Pharmacy, University of Wisconsin-Madison , Madison, Wisconsin 53705, United States.,Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
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27
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Tylinski M, Beasley MS, Chua YZ, Schick C, Ediger MD. Limited surface mobility inhibits stable glass formation for 2-ethyl-1-hexanol. J Chem Phys 2017; 146:203317. [DOI: 10.1063/1.4977787] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- M. Tylinski
- Department of Chemistry, University of Wisconsin–Madison, Madison, Wisconsin 53706, USA
| | - M. S. Beasley
- Department of Chemistry, University of Wisconsin–Madison, Madison, Wisconsin 53706, USA
| | - Y. Z. Chua
- Institute of Physics, University of Rostock, Albert-Einstein-Str. 23-24, 18051 Rostock, Germany and Competence Centre CALOR, Faculty of Interdisciplinary Research, University of Rostock, Albert-Einstein-Str. 25, 18051 Rostock, Germany
| | - C. Schick
- Institute of Physics, University of Rostock, Albert-Einstein-Str. 23-24, 18051 Rostock, Germany and Competence Centre CALOR, Faculty of Interdisciplinary Research, University of Rostock, Albert-Einstein-Str. 25, 18051 Rostock, Germany
| | - M. D. Ediger
- Department of Chemistry, University of Wisconsin–Madison, Madison, Wisconsin 53706, USA
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28
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Laventure A, Gujral A, Lebel O, Pellerin C, Ediger MD. Influence of Hydrogen Bonding on the Kinetic Stability of Vapor-Deposited Glasses of Triazine Derivatives. J Phys Chem B 2017; 121:2350-2358. [DOI: 10.1021/acs.jpcb.6b12676] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Audrey Laventure
- Département
de chimie, Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, Québec H3C 3J7, Canada
| | - Ankit Gujral
- Department
of Chemistry, University of Wisconsin−Madison, Madison, Wisconsin 53706, United States
| | - Olivier Lebel
- Department
of Chemistry and Chemical Engineering, Royal Military College of Canada, Kingston, Ontario K7K 7B4, Canada
| | - Christian Pellerin
- Département
de chimie, Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, Québec H3C 3J7, Canada
| | - M. D. Ediger
- Department
of Chemistry, University of Wisconsin−Madison, Madison, Wisconsin 53706, United States
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29
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Gómez J, Gujral A, Huang C, Bishop C, Yu L, Ediger MD. Nematic-like stable glasses without equilibrium liquid crystal phases. J Chem Phys 2017; 146:054503. [DOI: 10.1063/1.4974829] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
- Jaritza Gómez
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Ankit Gujral
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Chengbin Huang
- School of Pharmacy, University of Wisconsin-Madison, 777 Highland Avenue, Madison, Wisconsin 53705-2222, USA
| | - Camille Bishop
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Lian Yu
- School of Pharmacy, University of Wisconsin-Madison, 777 Highland Avenue, Madison, Wisconsin 53705-2222, USA
| | - M. D. Ediger
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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