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Janani H, Marxsen SF, Eck M, Mecking S, Tashiro K, Alamo RG. Polymorphism and Stretch-Induced Transformations of Sustainable Polyethylene-Like Materials. ACS Macro Lett 2024:201-206. [PMID: 38261790 DOI: 10.1021/acsmacrolett.3c00639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
Abstract
Herein we demonstrate that polyethylene-like bioderived, biodegradable, and fully recyclable unbranched aliphatic polyesters, such as PE-2,18, develop hexagonal crystal structures upon quenching from the melt to temperatures <∼50 °C and orthorhombic-like packing at higher quenching temperatures or after isothermal crystallization. Both crystal types are layered. While all-trans CH2 packing characterizes the structure of the orthorhombic-like form, there is significant conformational disorder in the staggered long CH2 sequences of the hexagonal crystals. On heating, the hexagonal crystals transform to the orthorhombic type at ∼60 °C via melt recrystallization, but no change is apparent during heating samples with the orthorhombic form up to the melting point (∼95 °C). The hexagonal structure is of interest not only because it develops under very rapid quenching from the melt but also because under uniaxial tensile deformation it undergoes a stretch-induced transformation to the orthorhombic structure. Compared to deformation of orthorhombic specimens that maintain the same crystal type, such transformation results in larger strains and enhanced strain hardening, thus representing a desired toughening mechanism for this type of polyethylene-like materials.
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Affiliation(s)
- Hamed Janani
- FAMU-FSU College of Engineering, Department of Chemical and Biomedical Engineering, 2525 Pottsdamer Street, Tallahassee, Florida 32310, United States
| | - Stephanie F Marxsen
- FAMU-FSU College of Engineering, Department of Chemical and Biomedical Engineering, 2525 Pottsdamer Street, Tallahassee, Florida 32310, United States
| | - Marcel Eck
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Stefan Mecking
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Kohji Tashiro
- Aichi Synchrotron Radiation Center, Knowledge Hub Aichi, Minami-Yamaguchi, Seto 489-0965, Japan
| | - Rufina G Alamo
- FAMU-FSU College of Engineering, Department of Chemical and Biomedical Engineering, 2525 Pottsdamer Street, Tallahassee, Florida 32310, United States
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Tafrishi H, Sadeghzadeh S, Ahmadi R. Molecular dynamics simulations of phase change materials for thermal energy storage: a review. RSC Adv 2022; 12:14776-14807. [PMID: 35702228 PMCID: PMC9112287 DOI: 10.1039/d2ra02183h] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 04/18/2022] [Indexed: 02/05/2023] Open
Abstract
Phase change materials (PCM) have had a significant role as thermal energy transfer fluids and nanofluids and as media for thermal energy storage. Molecular dynamics (MD) simulations, can play a significant role in addressing several thermo-physical problems of PCMs at the atomic scale by providing profound insights and new information. In this paper, the reviewed research is classified into five groups: pure PCM, mixed PCM, PCM containing nanofillers, nano encapsulated PCM, and PCM in nanoporous media. A summary of the equilibrium and non-equilibrium MD simulations of PCMs and their results is presented as well. The primary results of the simulated systems are demonstrated to be efficient in manufacturing phase change materials with better thermal energy storage features. The goals of these studies are to achieve higher thermal conductivity, higher thermal capacity, and lower density change, determine the melting point, and understand the molecular behaviors of PCM composites. A molecular dynamics-based grouping (PCM simulation table) was presented that is very useful for the future roadmap of PCM simulation. In the end, the PCFF force field is presented in detail and a case problem is studied for more clarity. The results show that simulating the PCMs with a similar strategy could be performed systematically. Results of investigations of thermal conductivity enhancement showed that this characteristic can be increased at the nano-scale by the orientation of PCM molecules.
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Affiliation(s)
- Hossein Tafrishi
- MSc Student of Energy Systems Engineering, School of Advanced Technologies, Iran University of Science and technology Tehran Iran
| | - Sadegh Sadeghzadeh
- Associate Professor of Nanotechnology Engineering, School of Advanced Technologies, Iran University of Science and Technology Tehran Iran
| | - Rouhollah Ahmadi
- Associate Professor of Energy Systems Engineering, School of Advanced Technologies, Iran University of Science and Technology Tehran Iran
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Mosquera-Vargas E, Marín C. Raman analysis of intermediate phases during melting and freezing in long-chain n-alkanes. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 269:120767. [PMID: 34952442 DOI: 10.1016/j.saa.2021.120767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 11/29/2021] [Accepted: 12/12/2021] [Indexed: 06/14/2023]
Abstract
Structural changes of the n-alkanes (n = 18, 20, 21, 22) have been investigated by Raman spectroscopy during the melting from solid phase to the intermediate transition phase to the molten phase. With increasing temperature docosane (C22) undergoes an orthorhombic-hexagonal (rotator, R) phase follow by an alpha (α) phase. In addition, the α phase as an intermediate transition between the solid and liquid phases is observed in heneicosane (C21). For eicosane (C20) and octadecane (C18) the transition from solid to liquid phase is almost instantaneous unlike docosane (C22) and heneicosane (C21) where the intermediate transitions are observed. During freezing from the liquid phase, the even n-alkanes show the rotator phase (R) a few degrees lower than melting and just before the crystalline solid phase. The intermediate phase transition temperature can be spectrally determined with the 1100-1350 cm-1 Raman region of the CH2 band.
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Affiliation(s)
- Edgar Mosquera-Vargas
- Grupo de Transiciones de Fase y Materiales Funcionales (GTFMF), Departamento de Física, Universidad del Valle, Santiago de Cali, Colombia; Centro de Excelencia en Nuevos Materiales (CENM), Universidad del Valle, A.A. 25360, Santiago de Cali, Colombia.
| | - Carlos Marín
- Department of Engineering Sciences & Materials, University of Puerto Rico, Mayagüez Campus, Mayagüez, PR 00680, USA.
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Inside out Approach to Rotator State in Hydrogen-Bonded System-Experimental and Theoretical Cross-Examination in n-Octanol. Int J Mol Sci 2022; 23:ijms23042138. [PMID: 35216257 PMCID: PMC8877557 DOI: 10.3390/ijms23042138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 02/08/2022] [Accepted: 02/11/2022] [Indexed: 12/02/2022] Open
Abstract
The experimental and theoretical description of premelting behavior is one of the most challenging tasks in contemporary material science. In this paper, n-octanol was studied using a multi-method approach to investigate it at macroscopic and molecular levels. The experimental infrared (IR) spectra were collected in the solid state and liquid phase at temperature range from −84∘C to −15 ∘C to detect temperature-related indicators of pretransitional phenomena. Next, the nonlinear dielectric effect (NDE) was measured at various temperatures (from −30 ∘C to −15 ∘C) to provide insight into macroscopic effects of premelting. As a result, a two-step mechanism of premelting in n-octanol was established based on experimental data. It was postulated that it consists of a rotator state formation followed by the surface premelting. In order to shed light onto molecular-level processes, classical molecular dynamics (MD) was performed to investigate the time evolution of the changes in metric parameters as a function of simulation temperature. The applied protocol enabled simulations in the solid state as well as in the liquid (the collapse of the ordered crystal structure). The exact molecular motions contributing to the rotator state formation were obtained, revealing an enabling of the rotational freedom of the terminal parts of the chains. The Car–Parrinello molecular dynamics (CPMD) was applied to support and interpret experimental spectroscopic findings. The vibrational properties of the stretching of OH within the intermolecular hydrogen bond were studied using Fourier transformation of the autocorrelation function of both dipole moments and atomic velocity. Finally, path integral molecular dynamics (PIMD) was carried out to analyze the quantum effect’s influence on the bridged proton position in the hydrogen bridge. On the basis of the combined experimental and theoretical conclusions, a novel mechanism of the bridged protons dynamics has been postulated—the interlamellar hydrogen bonding pattern, resulting in an additional OH stretching band, visible in the solid-state experimental IR spectra.
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Pocheć M, Krupka KM, Panek JJ, Orzechowski K, Jezierska A. Intermolecular Interactions and Spectroscopic Signatures of the Hydrogen-Bonded System-n-Octanol in Experimental and Theoretical Studies. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27041225. [PMID: 35209010 PMCID: PMC8878718 DOI: 10.3390/molecules27041225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 02/06/2022] [Accepted: 02/09/2022] [Indexed: 11/29/2022]
Abstract
n-Octanol is the object of experimental and theoretical study of spectroscopic signatures and intermolecular interactions. The FTIR measurements were carried out at 293 K for n-octanol and its deuterated form. Special attention was paid to the vibrational features associated with the O-H stretching and the isotope effect. Density Functional Theory (DFT) in its classical formulations was applied to develop static models describing intermolecular hydrogen bond (HB) and isotope effect in the gas phase and using solvent reaction field reproduced by Polarizable Continuum Model (PCM). The Atoms in Molecules (AIM) theory enabled electronic structure and molecular topology study. The Symmetry-Adapted Perturbation Theory (SAPT) was used for energy decomposition in the dimers of n-octanol. Finally, time-evolution methods, namely classical molecular dynamics (MD) and Car-Parrinello Molecular Dynamics (CPMD) were employed to shed light onto dynamical nature of liquid n-octanol with emphasis put on metric and vibrational features. As a reference, CPMD gas phase results were applied. Nuclear quantum effects were included using Path Integral Molecular Dynamics (PIMD) and a posteriori method by solving vibrational Schrödinger equation. The latter applied procedure allowed to study the deuterium isotope effect.
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Zhang R, Fall WS, Hall KW, Gehring GA, Zeng X, Ungar G. Roughening Transition and Quasi-continuous Melting of Monolayers of Ultra-long Alkanes: Why Bulk Polymer Melting Is Strongly First-Order. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c01377] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ruibin Zhang
- Department of Materials Science and Engineering, University of Sheffield, Sheffield S1 3JD, UK
- State Key Laboratory for Mechanical Behavior of Materials, Shaanxi International Research Centre for Soft Materials, Xi’an Jiaotong University, Xi’an 710049, China
- Department of Physics, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - William S. Fall
- State Key Laboratory for Mechanical Behavior of Materials, Shaanxi International Research Centre for Soft Materials, Xi’an Jiaotong University, Xi’an 710049, China
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, UK
- Institut Charles Sadron, Université de Strasbourg, CNRS, UPR 22, 67034 Strasbourg, France
| | - Kyle Wm. Hall
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Gillian A. Gehring
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, UK
| | - Xiangbing Zeng
- Department of Materials Science and Engineering, University of Sheffield, Sheffield S1 3JD, UK
| | - Goran Ungar
- Department of Materials Science and Engineering, University of Sheffield, Sheffield S1 3JD, UK
- State Key Laboratory for Mechanical Behavior of Materials, Shaanxi International Research Centre for Soft Materials, Xi’an Jiaotong University, Xi’an 710049, China
- Department of Physics, Zhejiang Sci-Tech University, Hangzhou 310018, China
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Arrigoni A, Brambilla L, Bertarelli C, Serra G, Tommasini M, Castiglioni C. P(VDF-TrFE) nanofibers: structure of the ferroelectric and paraelectric phases through IR and Raman spectroscopies. RSC Adv 2020; 10:37779-37796. [PMID: 35515179 PMCID: PMC9057215 DOI: 10.1039/d0ra05478j] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 09/30/2020] [Indexed: 11/27/2022] Open
Abstract
This study elucidates the complex morphology and the related spectroscopic response of poly(vinylidene fluoride-co-trifluoroethylene) copolymer, with 80% molar VDF content, namely P(VDF-TrFE) (80/20). We investigate the molecular structure, the morphology and the thermal behaviour of P(VDF-TrFE) samples obtained as electrospun nanofibers; we discuss their thermal evolution crossing the Curie temperature and the structure resulting after annealing, giving a comparison with P(VDF-TrFE) films. The new experimental data here obtained, combined with previous spectroscopic studies carried out on piezoelectric fluorinated polymers and copolymers, allow identifying spectroscopic markers sensitive to the molecular structure, the molecular orientation, the conformational defects and the kind of crystalline phase. We assign the vibrational modes localized on TrFE units by combining experimental observation and density functional calculations carried out on suitable molecular models. This work provides a sound set of diagnostic tools, which can be exploited for the assessment of structure/property relationships aimed at clarifying the molecular mechanisms leading to the piezoelectric performance of fluorinated copolymers.
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Affiliation(s)
- Alessia Arrigoni
- Dipartimento di Chimica, Materiali e Ingegneria Chimica "Giulio Natta", Politecnico di Milano, Piazza Leonardo da Vinci 32 20133 Milano Italy
| | - Luigi Brambilla
- Dipartimento di Chimica, Materiali e Ingegneria Chimica "Giulio Natta", Politecnico di Milano, Piazza Leonardo da Vinci 32 20133 Milano Italy
| | - Chiara Bertarelli
- Dipartimento di Chimica, Materiali e Ingegneria Chimica "Giulio Natta", Politecnico di Milano, Piazza Leonardo da Vinci 32 20133 Milano Italy
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia Via Pascoli 70/3 20133 Milano Italy
| | - Gianluca Serra
- Dipartimento di Chimica, Materiali e Ingegneria Chimica "Giulio Natta", Politecnico di Milano, Piazza Leonardo da Vinci 32 20133 Milano Italy
| | - Matteo Tommasini
- Dipartimento di Chimica, Materiali e Ingegneria Chimica "Giulio Natta", Politecnico di Milano, Piazza Leonardo da Vinci 32 20133 Milano Italy
| | - Chiara Castiglioni
- Dipartimento di Chimica, Materiali e Ingegneria Chimica "Giulio Natta", Politecnico di Milano, Piazza Leonardo da Vinci 32 20133 Milano Italy
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Havelcová M, Machovič V, Novák F, Lapčák L, Mizera J, Hendrych J. Chemical characterization of mountain forest soils: impact of long-term atmospheric deposition loadings (Czech-Polish-German border region). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:20344-20357. [PMID: 32239414 DOI: 10.1007/s11356-020-08558-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 03/23/2020] [Indexed: 06/11/2023]
Abstract
The composition of lipids in soil offers clues to soil degradation processes due their persistency and selectivity in soil, and close relation to long-term processes in the ecosystem, thanks to their role in cell membranes of organisms. Organic solvent-extractable compounds were recovered from soils collected at two sites differing in the degree of forest damage. Gas chromatography/mass spectroscopy and Fourier transform infrared spectroscopy were applied in order to characterize solvent-extractable lipids. Raman spectroscopy was also applied as it provides distinct advantages for determining the structural order of carbonaceous materials. The organic matter measurement techniques were combined with an established simultaneous multi-element measurement technique. Variations in individual soil horizons from the sites were reflected in the crystallinity of epicuticular waxes, presence of long-chain aliphatic hydrocarbons, concentrations of n-alkanes, saturated and unsaturated fatty acids, dicarboxylic acids, and in the content of aromatic structures, hydroxyl, ester, and carboxylic acid groups. The results are explained by differently transformed organic matter. The concentrations of elements in the soils were also affected by atmospheric depositions, including higher accumulations of arsenic and antimony, and lower contents of natural nutrients. These data have potential to be used as sensitive biogenic indicators of ecosystem damage by long-term atmospheric depositions.
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Affiliation(s)
- Martina Havelcová
- Institute of Rock Structure and Mechanics, AS CR V Holešovičkách 41, 182 09, Prague, Czech Republic.
| | - Vladimír Machovič
- Institute of Rock Structure and Mechanics, AS CR V Holešovičkách 41, 182 09, Prague, Czech Republic
- University of Chemistry and Technology Prague, Technická 5, 166 28, Prague, Czech Republic
| | - František Novák
- Technopark Kralupy, University of Chemistry and Technology Prague, 278 01, Kralupy nad Vltavou, Czech Republic
| | - Ladislav Lapčák
- University of Chemistry and Technology Prague, Technická 5, 166 28, Prague, Czech Republic
| | - Jiří Mizera
- Institute of Nuclear Physic, Řež 130, 250 68, Řež, Czech Republic
| | - Jiří Hendrych
- University of Chemistry and Technology Prague, Technická 5, 166 28, Prague, Czech Republic
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9
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Pezzotti G. Raman spectroscopy of biomedical polyethylenes. Acta Biomater 2017; 55:28-99. [PMID: 28359859 DOI: 10.1016/j.actbio.2017.03.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 03/01/2017] [Accepted: 03/09/2017] [Indexed: 12/14/2022]
Abstract
With the development of three-dimensional Raman algorithms for local mapping of oxidation and plastic strain, and the ability to resolve molecular orientation patterns with microscopic spatial resolution, there is an opportunity to re-examine many of the foundations on which our understanding of biomedical grade ultra-high molecular weight polyethylenes (UHMWPEs) are based. By implementing polarized Raman spectroscopy into an automatized tool with an improved precision in non-destructively resolving Euler angles, oxidation levels, and microscopic strain, we become capable to make accurate and traceable measurements of the in vitro and in vivo tribological responses of a variety of commercially available UHMWPE bearings for artificial hip and knee joints. In this paper, we first review the foundations and the main algorithms for Raman analyses of oxidation and strain of biomedical polyethylene. Then, we critically re-examine a large body of Raman data previously collected on different polyethylene joint components after in vitro testing or in vivo service, in order to shed new light on an area of particular importance to joint orthopedics: the microscopic nature of UHMWPE surface degradation in the human body. A complex scenario of physical chemistry appears from the Raman analyses, which highlights the importance of molecular-scale phenomena besides mere microstructural changes. The availability of the Raman microscopic probe for visualizing oxidation patterns unveiled striking findings related to the chemical contribution to wear degradation: chain-breaking and subsequent formation of carboxylic acid sites preferentially occur in correspondence of third-phase regions, and they are triggered by emission of dehydroxylated oxygen from ceramic oxide counterparts. These findings profoundly differ from more popular (and simplistic) notions of mechanistic tribology adopted in analyzing joint simulator data. Statement of Significance This review was dedicated to the theoretical and experimental evaluation of the commercially available biomedical polyethylene samples by Raman spectroscopy with regard to their molecular textures, oxidative patterns, and plastic strain at the microscopic level in the three dimensions of the Euclidean space. The main achievements could be listed, as follow: (i) visualization of molecular patterns at the surface of UHMWPE bearings operating against metallic components; (ii) differentiation between wear and creep deformation in retrievals; (iii) non-destructive mapping of oxidative patterns; and, (iv) the clarification of chemical interactions between oxide/non-oxide ceramic heads and advanced UHMWPE liners.
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Affiliation(s)
- Giuseppe Pezzotti
- Ceramic Physics Laboratory, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, 606-8585 Kyoto, Japan; Department of Orthopedic Surgery, Tokyo Medical University, 6-7-1 Nishi-Shinjuku, Shinjuku-ku, 160-0023 Tokyo, Japan; The Center for Advanced Medical Engineering and Informatics, Osaka University, Yamadaoka, Suita, 565-0871 Osaka, Japan; Department of Molecular Cell Physiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, 465 Kajii-cho, Kawaramachi dori, 602-0841 Kyoto, Japan.
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Corsetti S, Rabl T, McGloin D, Kiefer J. Intermediate phases during solid to liquid transitions in long-chain n-alkanes. Phys Chem Chem Phys 2017; 19:13941-13950. [PMID: 28513676 PMCID: PMC6040280 DOI: 10.1039/c7cp01468f] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 05/03/2017] [Indexed: 12/24/2022]
Abstract
The solid to liquid phase transition of n-alkanes with more than ten carbon atoms is an interesting phenomenon relevant to many fields, from cosmetics to automotive. Here we report Raman spectroscopy of tetradecane, pentadecane and hexadecane as a function of temperature. In order to gain information on the structural changes that the hydrocarbons undergo during melting, and to determine the temperature and the speed at which the phase change occurs, their temperature-dependent Raman spectra are acquired. The spectra are analysed not only with respect to frequency shifts, band widths, and intensity ratio of certain bands, but also using a principal component analysis. The spectroscopic data suggest that the solid to liquid phase transition in hexadecane, differently from tetradecane and pentadecane, is almost instantaneous. Tetradecane shows a slightly faster transition than pentadecane. In addition, a rotator phase as an intermediate state between the liquid and crystalline solid phases is identified in pentadecane. Different characteristic features in the solid spectra of the hydrocarbons relate tetradecane and hexadecane to a tryclinic crystalline structure, and pentadecane to an orthorhombic structure.
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Affiliation(s)
- Stella Corsetti
- SUPA, School of Science & Engineering, University of Dundee, Nethergate, Dundee, DD1 4HN, Scotland, UK.
| | - Thomas Rabl
- SUPA, School of Science & Engineering, University of Dundee, Nethergate, Dundee, DD1 4HN, Scotland, UK. and Drug Discovery Unit, College of Life Sciences, University of Dundee, Dow Street, Dundee, DD1 5EH, Scotland, UK
| | - David McGloin
- SUPA, School of Science & Engineering, University of Dundee, Nethergate, Dundee, DD1 4HN, Scotland, UK.
| | - Johannes Kiefer
- Technische Thermodynamik, Universität Bremen, Badgasteiner Str. 1, 28359 Bremen, Germany and School of Engineering, University of Aberdeen, Aberdeen, AB24 3UE, Scotland, UK
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Yao X, Cseh L, Zeng X, Xue M, Liu Y, Ungar G. Body-centred cubic packing of spheres - the ultimate thermotropic assembly mode for highly divergent dendrons. NANOSCALE HORIZONS 2017; 2:43-49. [PMID: 32260676 DOI: 10.1039/c6nh00155f] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We have synthesized sodium tris(alkoxy)benzoates in which one of the three alkyl chains branches further into three C18H37 chains. These AB5 hyperbranched minidendrons melt directly into a body-centred cubic (BCC) mesophase formed by spherical "micelles". In contrast, their non-branched counterparts display various mesophases before they turn into BCC upon heating. This agrees with the predictions from a numerical geometric model that relates the shape of the molecular wedge to the type of mesophase they adopt. The spheres were found to shrink in volume upon heating and expand upon cooling, as molecules, in some cases nearly half of them, are ejected and reintegrated in the spheres. The ejection of dendrons is caused by their lateral thermal expansion. The BCC appears to be the ultimate mesophase for the extremely divergent wedges such as the hyperbranched minidendrons. In dendrons with chains of unequal length, the sphere size is fixed by the shorter chains, the longer ones back-folding or interdigitating to effectively widen the wedge. This new understanding of their assembly will help in designing new dendrons, e.g. for better encapsulation of guest molecules.
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Affiliation(s)
- Xiaohong Yao
- Department of Physics, Zhejiang Sci-Tech University, Xiasha College Park, Hangzhou 310018, China
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12
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Galimberti D, Milani A, Maschio L, Castiglioni C. Intermolecular modulation of IR intensities in the solid state. The role of weak interactions in polyethylene crystal: A computational DFT study. J Chem Phys 2016; 145:144901. [PMID: 27782503 DOI: 10.1063/1.4964500] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Density functional theory calculations with periodic boundary conditions are exploited to study the infrared spectrum of crystalline polyethylene. Spectral changes lead by the intermolecular packing in the orthorhombic three-dimensional crystal are discussed by means of a careful comparison with calculations carried out for an isolated polymer chain in the all-trans conformation, described as an ideal one-dimensional crystal. The results are analyzed in the framework of the "oligomer approach" through the modelling of the IR spectrum of n-alkanes of different lengths. The study demonstrates that a relevant absorption intensity modulation of CH2 deformation transitions takes place in the solid state. This finding suggests a new interpretation for the experimental evidences collected in the past by means of IR intensity measurement during thermal treatment. Moreover, the comparison between calculations for 3-D crystal and for the isolated polyethylene chain (1-D crystal) allows to put in evidence the effect of the local electric field on the computed infrared intensities. This observation provides guidelines for the comparison between infrared absorption intensities predicted for an isolated unit and for a molecule belonging to a crystal, through the introduction of suitable correction factors based on the refraction index of the material and depending on the dimensionality of such units (0D-molecule; 1D-polymer; 2D-slab).
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Affiliation(s)
- Daria Galimberti
- LAMBE CNRS UMR8587, Laboratoire Analyse et Modélisation pour la Biologie et l'Environnement, Université d'Evry val d'Essonne, Boulevard F. Mitterrand, Bat Maupertuis, 91025 Evry, France
| | - Alberto Milani
- Dipartimento di Chimica, Materiali e Ingegneria Chimica Giulio Natta, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Lorenzo Maschio
- Dipartimento di Chimica, Università di Torino and NIS (Nanostructured Interfaces and Surfaces) Centre, Via P. Giuria 5, 10125 Torino, Italy
| | - Chiara Castiglioni
- Dipartimento di Chimica, Materiali e Ingegneria Chimica Giulio Natta, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
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Kotula AP, Walker ARH, Migler KB. Raman analysis of bond conformations in the rotator state and premelting of normal alkanes. SOFT MATTER 2016; 12:5002-5010. [PMID: 27174157 PMCID: PMC4973810 DOI: 10.1039/c6sm00182c] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We perform Raman spectroscopic measurements on normal alkanes (CnH2n+2) to quantify the n dependence of the conformational disorder that occurs below the melt temperature. We employ a three-state spectral analysis method originally developed for semi-crystalline polyethylene that posits crystalline, amorphous, and non-crystalline consecutive trans (NCCT) conformations to extract their respective mass fractions. For the alkanes studied that melt via a rotator phase (21 ≤n≤ 37), we find that conformational disorder can be quantified by the loss of NCCT mass fraction, which systematically decreases with increasing chain length. For those that melt directly via the crystal phase (n≥ 40), we observe NCCT conformational mass fractions that are independent of chain length but whose disordered mass fraction increases with length. These complement prior IR measurements which measure disorder via gauche conformations, but have not been able to measure the mass fraction of this disorder as a function of n. An interesting feature of the three-state analysis when applied to alkanes is that the measured fraction of disordered chain conformations in the rotator phase of (10 to 30)% greatly exceeds the mass fraction of gauche bonds (1 to 7)% as measured from IR; we reconcile this difference through DFT calculations.
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Affiliation(s)
- Anthony P Kotula
- Materials Science & Engineering Division, NIST, Gaithersburg, Maryland 20899, USA.
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15
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Brambilla L, Tommasini M, Botiz I, Rahimi K, Agumba JO, Stingelin N, Zerbi G. Regio-Regular Oligo and Poly(3-hexyl thiophene): Precise Structural Markers from the Vibrational Spectra of Oligomer Single Crystals. Macromolecules 2014. [DOI: 10.1021/ma501614c] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Luigi Brambilla
- Dipartimento
di Chimica, Materiali e Ingegneria Chimica “G. Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano Italy
| | - Matteo Tommasini
- Dipartimento
di Chimica, Materiali e Ingegneria Chimica “G. Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano Italy
| | - Ioan Botiz
- Nanobiophotonics
and Laser Microspectroscopy Center, Faculty of Physics and Interdisciplinary
Research Institute in Bio-Nano-Sciences, Babes-Bolyai University, Treboniu Laurian Street 42, Cluj Napoca 400271, Romania
- Department
of Materials, Imperial College London, Exhibition Road, London, SW7 2AZ, U.K
| | - Khosrow Rahimi
- DWI-Leibniz
Institute for Interactive Materials, RWTH Aachen University, 52074 Aachen, Germany
| | - John O. Agumba
- Institute
of Physics, University of Freiburg, Hermann-Herder Strasse 3, Freiburg 79104, Germany
| | - Natalie Stingelin
- Department
of Materials, Imperial College London, Exhibition Road, London, SW7 2AZ, U.K
| | - Giuseppe Zerbi
- Dipartimento
di Chimica, Materiali e Ingegneria Chimica “G. Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano Italy
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16
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Lüttschwager NOB, Suhm MA. Stretching and folding of 2-nanometer hydrocarbon rods. SOFT MATTER 2014; 10:4885-4901. [PMID: 24866111 DOI: 10.1039/c4sm00508b] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Linear alkanes CnH2n+2 in vacuum isolation are finite models for an infinite polyethylene chain. Using spontaneous Raman scattering in supersonic jet expansions for n = 13-21 in different spectral ranges, we determine the minimal chain length nh for the cohesion-driven folding of the preferred extended all-trans conformation into a hairpin structure. We treat fully stretched all-trans alkanes as molecular "nanorods" and derive Young's modulus E for the stretching of an isolated single-strand polyethylene fibre by extrapolating the longitudinal acoustic mode to infinite chain length. Two key quality parameters for accurate intra- and intermolecular force fields of hydrocarbons (nh = 18 ± 1, E = 305 ± 5 GPa) are thus derived with high accuracy from experimental spectroscopy.
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Affiliation(s)
- Nils O B Lüttschwager
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstr. 6, 37077 Göttingen, Germany.
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17
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Moschovi AM, Dracopoulos V, Nikolakis V. Inter- and intramolecular interactions in imidazolium protic ionic liquids. J Phys Chem B 2014; 118:8673-83. [PMID: 24971830 DOI: 10.1021/jp412352k] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The interactions of alkyl substituted imidazolium bis(trifluoromethanolsulfonyl)imide protic ionic liquids (PILs) HCnImNTf2 (n = 0-12) were studied using vibrational spectroscopy (FT-IR/ATR and FT-Raman) and differential scanning calorimetry (DSC). The effect of alkyl substituent length (n = 0-12) and temperature on the relative magnitude of the different interactions is elucidated. For short carbon alkyl chains (n < 3), the PIL structure is affected from intramolecular interaction caused from the induction effect (+I) due to the chain substituent of the imidazolium ring, while for PILs with n > 3 the van der Waals forces between the chains and π-π interaction between neighboring imidazolium rings become important. The tendency of reducing the melting point and increasing glass transition values with the lengthening of the alkyl chain was also noticed as a result the increasing contribution of the van der Waals forces to the overall interactions. Finally, we also show that the conformational isomerism of the anion (expressed by ΔHeq) is a good indicator of the relative magnitude of the interactions. When Coulombic interactions are predominant, the trans conformer is the most probable, while when other type of interactions (HB, vdW, etc.) become important the cis conformer is favored.
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Affiliation(s)
- Anastasia Maria Moschovi
- Department of Chemical Engineering, University of Patras , Karatheodori 1, University Campus, GR-26500 Patras, Greece
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18
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Roche C, Sun HJ, Prendergast ME, Leowanawat P, Partridge BE, Heiney PA, Araoka F, Graf R, Spiess HW, Zeng X, Ungar G, Percec V. Homochiral columns constructed by chiral self-sorting during supramolecular helical organization of hat-shaped molecules. J Am Chem Soc 2014; 136:7169-85. [PMID: 24758745 DOI: 10.1021/ja5035107] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A library of dendronized cyclotriveratrylene (CTV) crowns substituted with chiral, racemic, or achiral peripheral alkyl chains, including enantiopure R and S branched alkyls, "racemic by mixture", "racemic by synthesis", n-octyl, and n-dodecyl groups was synthesized. In solvophobic solvents and in bulk they self-assemble in helical columns. Their solution and bulk shape-persistent supramolecular structures were determined by a complementary combination of circular dichroism (CD) and UV in solution and thin film, microspot CD in thin film, differential scanning calorimetry combined with fiber X-ray diffraction, computer simulation, and molecular models. In solution, self-assembly via a cooperative mechanism generates single-handed columns from enantiopure CTVs and mixtures of right- and left-handed columns from racemic by mixture, racemic by synthesis, other combinations of R and S, and even from achiral compounds. In bulk state all supramolecular columns form a 3D hexagonal crystalline phase, Φ(h)(k) (P6₃ symmetry), that can be obtained only from single-handed columns and a columnar hexagonal 2D liquid crystal, Φ(h). The highest order Φ(h)(k) consists of enantiopure single-handed columns that are slightly distorted 12-fold triple helices. The "hat-shaped" dendronized CTV assembles in bent-branch pine-tree columns that allow interdigitation of alkyl groups in adjacent columns regardless of their direction. Enantiomerically rich, racemic, and achiral compositions undergo deracemization in the crystal state by transfer of the transient disc-like conformer of dendronized CTV from column to column during crown inversion. Solid state NMR experiments identified motional processes that allow such transfer. This unprecedented supramolecular chiral self-sorting will impact the creation of functions in complex systems.
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Affiliation(s)
- Cécile Roche
- Roy & Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania , Philadelphia, Pennsylvania 19104-6323, United States
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19
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Vezvaie M, Brosseau CL, Lipkowski J. Electrochemical SERS study of a biomimetic membrane supported at a nanocavity patterned Ag electrode. Electrochim Acta 2013. [DOI: 10.1016/j.electacta.2013.03.139] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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20
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Petruk AA, Sosa Morales MC, Álvarez RMS. Iodothyronine-phospholipid interactions in the lipid gel phase probed by Raman spectral markers. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 112:403-409. [PMID: 23694898 DOI: 10.1016/j.saa.2013.04.094] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 04/18/2013] [Accepted: 04/24/2013] [Indexed: 06/02/2023]
Abstract
A better understanding of the structural effects induced by thyroid hormones in model membranes is attained by Raman spectroscopy. The interactions of T3 and T4 with multilamellar vesicles of dipalmytoylphosphatidylcholine (DPPC) in the gel phase are characterized by analyzing the spectral behavior of the C-H and C-C stretching vibrations of the acyl chains. The spectra evidence an increase in the relative number of gauche conformation, which indicates the hormones are able to penetrate into the hydrophobic region of the bilayer and partially alter the lipid structure. In addition, the density packing of the acyl chains appears increased and the rotational mobility of the terminal methylene groups is slightly reduced in the iodothyronine/DPPC mixtures. These effects are interpreted in terms of the transition to an interdigitated phase due to the hormone incorporation to the membrane. The polar heads of the lipids also interact with the hormone, as evidenced by the PO2(-) symmetric stretching band.
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Affiliation(s)
- Ariel A Petruk
- Instituto Superior de Investigaciones Biológicas (CONICET-UNT), Chacabuco 461, S.M. de Tucumán, Tucumán T4000ILI, Argentina
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21
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Motoyama M, Chikuni K, Narita T, Aikawa K, Sasaki K. In situ Raman spectrometric analysis of crystallinity and crystal polymorphism of fat in porcine adipose tissue. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:69-75. [PMID: 23230815 DOI: 10.1021/jf3034896] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
From the adipose tissues of pork carcasses stored in a refrigerator, Raman spectra were observed in situ by a portable Raman spectrometer. The observed Raman spectra, which were almost completely due to fat, showed clear dependence on the refrigeration time and carcass temperature. This dependence reflected an increase in the crystallinity of the fat and a change in the fraction of the β' polymorph. Evidence of changes in the packing order of the aliphatic chains of acylglycerol molecules was obtained, and the changes lasted for a long time after the temperature reached the lowest point (4.3 °C). Possibilities of using Raman spectrometry as a tool for routine monitoring of the conditions of carcasses as well as for research on the improvement of the mechanical strength of the adipose tissue are discussed.
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Affiliation(s)
- Michiyo Motoyama
- Institute of Livestock and Grassland Science, National Agricultural Research Organization (NARO), Ibaraki, Japan.
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22
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Quarti C, Milani A, Castiglioni C. Ab Initio Calculation of the IR Spectrum of PTFE: Helical Symmetry and Defects. J Phys Chem B 2013; 117:706-18. [DOI: 10.1021/jp3102145] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Claudio Quarti
- Politecnico di Milano − Dip. Chimica, Materiali
e Ing. Chimica “G. Natta”, P.zza Leonardo da Vinci 32,
I-20133 Milano, Italy
| | - Alberto Milani
- Politecnico di Milano − Dip. Chimica, Materiali
e Ing. Chimica “G. Natta”, P.zza Leonardo da Vinci 32,
I-20133 Milano, Italy
| | - Chiara Castiglioni
- Politecnico di Milano − Dip. Chimica, Materiali
e Ing. Chimica “G. Natta”, P.zza Leonardo da Vinci 32,
I-20133 Milano, Italy
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23
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Brotin T, Cavagnat D, Berthault P, Montserret R, Buffeteau T. Water-Soluble Molecular Capsule for the Complexation of Cesium and Thallium Cations. J Phys Chem B 2012; 116:10905-14. [DOI: 10.1021/jp305110k] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Thierry Brotin
- Laboratoire de Chimie de l’ENS LYON (UMR 5182-CNRS), École
Normale Supérieure de Lyon, 46 Allée d’Italie,
69364 Lyon, France
| | - Dominique Cavagnat
- Institut des Sciences Moléculaires (UMR 5255-CNRS), Université
de Bordeaux 1, 351 Cours de la Libération, 33405 Talence, France
| | - Patrick Berthault
- Laboratoire Structure et Dynamique par Résonance Magnétique (UMR 3299-CEA/CNRS), CEA Saclay, IRAMIS, SIS2M, 91191 Gif sur Yvette, France
| | - Roland Montserret
- Institut de Biologie et Chimie des Protéines (UMR 5086-CNRS), BMSSI,
Université de Lyon 1, 7 Passage du Vercors, 69367 Lyon, France
| | - Thierry Buffeteau
- Institut des Sciences Moléculaires (UMR 5255-CNRS), Université
de Bordeaux 1, 351 Cours de la Libération, 33405 Talence, France
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24
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Intramolecular interactions in polymethylenic chains with polar end groups: The spectroscopic signature. J Mol Struct 2012. [DOI: 10.1016/j.molstruc.2011.10.041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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25
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Ahmed S, Nikolov Z, Wunder SL. Effect of Curvature on Nanoparticle Supported Lipid Bilayers Investigated by Raman Spectroscopy. J Phys Chem B 2011; 115:13181-90. [DOI: 10.1021/jp205999p] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Selver Ahmed
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Zhorro Nikolov
- College of Engineering, Drexel University, Philadelphia, Pennsylvania 19104, United States
| | - Stephanie L. Wunder
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, United States
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26
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Porzio W, Scavia G, Arnautov S, Conzatti L, Charmet J, Laux E, Keppner H, Zerbi G, Brambilla L, Bolognesi A. Nanoscale structure and morphology of thin films of poly(2-chloroxylylene) synthesized by the CVD method on different liquids. Eur Polym J 2011. [DOI: 10.1016/j.eurpolymj.2011.06.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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27
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Interaction of the cationic peptide bactenecin with mixed phospholipid monolayers at the air-water interface. J Colloid Interface Sci 2011; 359:279-88. [PMID: 21501845 DOI: 10.1016/j.jcis.2011.03.081] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2010] [Revised: 03/26/2011] [Accepted: 03/29/2011] [Indexed: 01/02/2023]
Abstract
The initial mechanism by which antimicrobial peptides target microbes occurs via electrostatic interactions; however, the mechanism is not well understood. We investigate the interaction of the antimicrobial peptide bactenecin with a 50:50 w:w% 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-dimyristoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (DMPG) phospholipid mixture at the air-water interface with different NaCl concentrations (0.01, 0.05, 0.1, 0.5 M) in the subphase. A larger shift of DPPC:DMPG isotherms was obtained for 0.1 M salt concentration at lower and higher pressures, demonstrating the influence of the negative charge of DMPG molecules and the screening of the electrostatic interaction by the salt concentration. Raman spectroscopy of monolayers demonstrated the presence of cysteine-cysteine bridges in bactenecin loops. The peptide adsorption in DPPC:DMPG monolayers observed by AFM images suggests a self-assembled aggregation process, starting with filament-like networks. Domains similar to carpets were formed and pore structures were obtained after a critical peptide concentration, according to the carpet model.
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28
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Kobayashi M, Kobayashi T, Cho Y, Kaneko F. States of molecular assembly and physical properties of crystalline long-chain compounds studied by vibrational spectroscopy. ACTA ACUST UNITED AC 2011. [DOI: 10.1002/masy.19860050103] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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29
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Zhou Y, Shi H, Zhao Y, Men Y, Jiang S, Rottstegge J, Wang D. Confined crystallization and phase transition in semi-rigid chitosan containing long chain alkyl groups. CrystEngComm 2011. [DOI: 10.1039/c0ce00165a] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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30
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Strobl GR, Schwickert H, Trzebiatowski T. Molecular Motion, Defect Structures and Phase Transitions in Oligomer Crystals. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19830870321] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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31
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Paudel K, Knoll H, Chandrasekhar M, Guha S. Tuning Intermolecular Interactions in Dioctyl-Substituted Polyfluorene via Hydrostatic Pressure. J Phys Chem A 2010; 114:4680-8. [DOI: 10.1021/jp911778r] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- K. Paudel
- Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211
| | - H. Knoll
- Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211
| | - M. Chandrasekhar
- Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211
| | - S. Guha
- Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211
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32
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Mendelsohn R, Mao G, Flach CR. Infrared reflection-absorption spectroscopy: principles and applications to lipid-protein interaction in Langmuir films. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1798:788-800. [PMID: 20004639 DOI: 10.1016/j.bbamem.2009.11.024] [Citation(s) in RCA: 160] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2009] [Revised: 11/19/2009] [Accepted: 11/24/2009] [Indexed: 01/08/2023]
Abstract
Infrared reflection-absorption spectroscopy (IRRAS) of lipid/protein monolayer films in situ at the air/water interface provides unique molecular structure and orientation information from the film constituents. The technique is thus well suited for studies of lipid/protein interaction in a physiologically relevant environment. Initially, the nature of the IRRAS experiment is described and the molecular structure information that may be obtained is recapitulated. Subsequently, several types of applications, including the determination of lipid chain conformation and tilt as well as elucidation of protein secondary structure are reviewed. The current article attempts to provide the reader with an understanding of the current capabilities of IRRAS instrumentation and the type of results that have been achieved to date from IRRAS studies of lipids, proteins, and lipid/protein films of progressively increasing complexity. Finally, possible extensions of the technology are briefly considered.
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Affiliation(s)
- Richard Mendelsohn
- Department of Chemistry, Newark College, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA.
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33
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Innocenzi P, Malfatti L, Piccinini M, Marcelli A. Evaporation-Induced Crystallization of Pluronic F127 Studied in Situ by Time-Resolved Infrared Spectroscopy. J Phys Chem A 2009; 114:304-8. [DOI: 10.1021/jp908162z] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Plinio Innocenzi
- Laboratorio di Scienza dei Materiali e Nanotecnologie, D.A.P., Università di Sassari, and CR-INSTM, Palazzo del Pou Salid, Piazza Duomo 6, 07041 Alghero (Sassari), Italy
| | - Luca Malfatti
- Laboratorio di Scienza dei Materiali e Nanotecnologie, D.A.P., Università di Sassari, and CR-INSTM, Palazzo del Pou Salid, Piazza Duomo 6, 07041 Alghero (Sassari), Italy
| | - Massimo Piccinini
- Porto Conte Ricerche S.r.l., SP 55 Porto Conte/Capo Caccia km 8,400, 07041 Alghero (SS), Italy
| | - Augusto Marcelli
- Laboratori Nazionali di Frascati—INFN, Via E. Fermi 40, 00044, Frascati, Italy
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34
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Sandras F, Pézolet M, Marion D, Grauby-Heywang C. Raman study of the puroindoline-a/lysopamitoylphosphatidylcholine interaction in free standing black films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:8181-8186. [PMID: 19397273 DOI: 10.1021/la9005086] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The conformation of puroindoline-a (PIN-a), a protein extracted from wheat endosperm, in free-standing black films has been studied using confocal Raman spectroscopy. This protein is characterized by the presence in its sequence of a unique tryptophan (Trp)-rich domain and of five disulfide bridges stabilizing its three-dimensional structure. PIN-a is able to form free-standing films, which are very stable in time, because of its remarkable surface-active properties. These films become black in a few hours and are characterized by the presence of numerous aggregates. Their Raman spectra show major modifications of the PIN-a structure as compared to the solid form, such as the formation of beta-sheets or unordered structures, the modification of the environment of the Trp domain and, the conformation of disulfide bridges. These modifications are in agreement with an unfolding of the protein at the interfaces of the film and suggest that the Trp domain is involved in the aggregation. We have also studied the influence of increasing amounts of lysopalmitoylphosphatidylcholine (LPC) into the films. The direct observation of these mixed films shows that LPC inhibits the formation of PIN-a aggregates and that the conformation of PIN-a is strongly correlated to the LPC/PIN-a molar ratio. Raman spectroscopy also shows that PIN-a disturbs the highly organized arrangement of LPC molecules in the film.
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Affiliation(s)
- Florent Sandras
- Centre de Physique Moleculaire Optique et Hertzienne, 33405 Talence cedex, France
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35
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Watanabe S, Noda I, Ozaki Y. Thermally induced conformational changes in polyethylene studied by two-dimensional near-infrared–infrared hetero-spectral correlation spectroscopy. J Mol Struct 2008. [DOI: 10.1016/j.molstruc.2008.01.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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36
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Polymorphic transformations of C26H54 and C28H58 n-paraffins as typical rotator substances. J STRUCT CHEM+ 2007. [DOI: 10.1007/s10947-007-0099-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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37
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Meier RJ, Csiszár A, Klumpp E. On the interpretation of the 1100 cm(-1) Raman band in phospholipids and other alkyl-containing molecular entities. J Phys Chem B 2007; 110:5842-4. [PMID: 16553388 DOI: 10.1021/jp060420w] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The long-standing issue on the interpretation of a Raman band at 1100 cm(-1) is discussed. By combining observations from studies on lipid bilayers, alkanes, and polyethylenes, one can now definitely assign this band to the presence of isolated gauche bonds. In addition, we discuss the use of an order parameter S(trans) in lipid bilayer structures.
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38
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Shi H, Zhao Y, Jiang S, Xin JH, Rottstegge J, Xu D, Wang D. Order–disorder transition in eicosylated polyethyleneimine comblike polymers. POLYMER 2007. [DOI: 10.1016/j.polymer.2007.03.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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39
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40
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Volz C, Arif M, Guha S. Conformations in dioctyl substituted polyfluorene: A combined theoretical and experimental Raman scattering study. J Chem Phys 2007; 126:064905. [PMID: 17313242 DOI: 10.1063/1.2434976] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The structural properties of polyfluorenes (PF) are extremely sensitive to the choice of functionalizing side chains. Dioctyl substituted PF (PF8) adopts metastable structures that depend upon the thermal history and choice of solvents used in film forming conditions. We present a detailed study of the changes in the backbone and side chain morphology in PF8, induced by the various crystallographic phases, using Raman scattering techniques. The vibrational frequencies and intensities of fluorene oligomers are calculated using hybrid density-functional theory with a 3-21G(*) basis set. The alkyl side chains are modeled as limiting conformations: all anti, anti-gauche-gauche, and end gauche representations. The calculated vibrational spectra of single chain oligomers in conjunction with our experimental results demonstrate the beta phase, which is known to originate in regions of enhanced chain planarity as a direct consequence of the alkyl side chain conformation.
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Affiliation(s)
- C Volz
- Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA
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41
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de Silva DSM, Zeng XB, Ungar G, Spells SJ. On Perpendicular and Tilted Chains in Lamellar Crystals. J MACROMOL SCI B 2007. [DOI: 10.1081/mb-120021615] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- D. S. M. de Silva
- a Department of Engineering Materials , University of Sheffield , Sheffield, UK
| | - Xiang-bing Zeng
- a Department of Engineering Materials , University of Sheffield , Sheffield, UK
| | - Goran Ungar
- a Department of Engineering Materials , University of Sheffield , Sheffield, UK
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Gruger A, Vogel-weill C. Étude Structurale par Microspectrométries Raman et Infrarouge de Figures Myéliniques Formées á Partir des Systémes Acide 2-g Octadécénoique/Solution D'Hydrazine 5M et Cholesterol Monohydraté/Solution Saturée d'Oléate de Sodium. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/10587259408046930] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- A. Gruger
- a Laboratoire de Spectrochimie Infrarouge et Raman , CNRS, 2 rue Henri Dunant, 94320 , Thiais , France
| | - C. Vogel-weill
- a Laboratoire de Spectrochimie Infrarouge et Raman , CNRS, 2 rue Henri Dunant, 94320 , Thiais , France
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43
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Gruger A, Vogel-weill C. Étude de la Conformation des Chaines Hydrocarbonées des Acides Z-9 Octadécénoique,† E-9 Octadécénoique† et n-Nonanoique dans L'état Liquide par Spectrométries Raman et Infrarouge. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/10587259408046929] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Alain Gruger
- a LASIR-CRNS-2 , rue Henri Dunant, 94320 , Thiais , France
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44
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Fukuhara K, Kumamoto H, Matsuura H. Molecular Conformation and Melting Behavior of Alkyl/Oligo(oxyethylene)/Alkyl Triblock Position Isomers: Effect of the Position of an Oligo(oxyethylene) Block. J Phys Chem B 2006; 110:16239-47. [PMID: 16913749 DOI: 10.1021/jp061564d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The molecular conformation and melting behavior of triblock position isomers H(CH(2))(k)(OCH(2)CH(2))(4)O(CH(2))(12)(-)(k)H (abbreviated as C(k)E(4)C(12)(-)(k)) with k = 6-11 have been studied by infrared spectroscopy and differential scanning calorimetry (DSC), with focus on the effect of the position of an oligo(oxyethylene) block in the molecule. The analysis of infrared spectra has revealed that the stable molecular form changes from a fully planar structure (gamma form) to a planar/helical/planar structure (beta form) with a change of the position of the tetrakis(oxyethylene) block from the center to the end of the molecule. The DSC measurements have shown that the melting points of the gamma-form solid decrease and the melting points of the beta-form solid increase with a shift of the tetrakis(oxyethylene) block toward the terminal of the molecule. The stabilities of the two molecular forms change over between k = 8 and 9. C(8)E(4)C(4) and C(9)E(4)C(3) exhibit contrasting conformational behavior with temperature; when the temperature is increased, the metastable beta form of C(8)E(4)C(4) transforms into the stable gamma form, while the metastable gamma form of C(9)E(4)C(3) transforms into the stable beta form. The metastable gamma form with a planar oligo(oxyethylene) block is a new finding in the present work. The experimental results of the stabilities of molecular forms are explained by the relative stabilities of partial crystal lattices formed by the alkyl and oligo(oxyethylene) blocks.
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Affiliation(s)
- Koichi Fukuhara
- Department of Chemistry, Graduate School of Science, Hiroshima University, Kagamiyama, Higashi-Hiroshima 739-8526, Japan.
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45
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Baonza VG, Taravillo M, Cazorla A, Casado S, Cáceres M. n-pentanol at high pressures: Rotational isomerism in the liquid phase and the liquid-solid phase transition. J Chem Phys 2006; 124:044508. [PMID: 16460186 DOI: 10.1063/1.2149855] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The vibrational spectrum of liquids constituted of chain molecules is difficult to analyze because it may have contributions of different rotational isomers. In turn, with a proper vibrational assignment, this feature allows us to extract information about the effect of temperature or pressure on the molecular conformations in the liquid state. In this regard, the information on the vibrational spectrum in the solid phase greatly simplifies the vibrational analysis of the different rotational conformers existing in the liquid, as the molecules usually present all-trans conformations in the crystalline state. Here we report room-temperature Raman experiments on n-pentanol performed in a sapphire-anvil cell up to 3 GPa. A detailed analysis of the liquid-solid phase transition occurring at 1.3 GPa is provided. The analysis of the Raman spectrum in the solid phase allows the identification of the bands due to the different rotational isomers present in the liquid. The analysis of the spectral region corresponding to skeletal vibrations of the carbon chain (800-1200 cm(-1)) indicates that gauche conformers are promoted by the application of pressure. The analysis of the intensity ratio of those bands assigned to trans and gauge conformations is used to calculate the change in molecular volume ascribed to the trans-gauge isomerization process. We find a value similar to that found in n-alkanes, i.e., -0.88 cm(3) mol(-1). In addition, we find indication that pressure varies the proportions of the different gauge conformers. Thus, it appears that the GTTt to TGTt transition in the carbon chain is favored at high pressures. As expected, a smaller change in the molecular volume accompanies this conformation change.
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Affiliation(s)
- V G Baonza
- Departamento de Química Física I, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain.
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46
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Arif M, Volz C, Guha S. Chain morphologies in semicrystalline polyfluorene: evidence from Raman scattering. PHYSICAL REVIEW LETTERS 2006; 96:025503. [PMID: 16486593 DOI: 10.1103/physrevlett.96.025503] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2005] [Indexed: 05/06/2023]
Abstract
The beta phase in di-octyl substituted polyfluorene (PF8) exhibits a surprising level of conformational order at nanometer length scales compared to other phases. We present Raman scattering studies of PF8 as a function of thermal cycling, which establishes a connection between the conformational isomers and the side and main chain morphology. Density-functional calculations of the vibrational spectra of single chain oligomers in conjunction with the experimental results demonstrate the incompatibility of the beta phase with the overall alpha crystalline phase in PF8.
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Affiliation(s)
- M Arif
- Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA
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47
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Wang Y, Marques EF. Thermotropic Phase Behavior of Cationic Gemini Surfactants and Their Equicharge Mixtures with Sodium Dodecyl Sulfate. J Phys Chem B 2005; 110:1151-7. [PMID: 16471657 DOI: 10.1021/jp0552729] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The lyotropic phase behavior for the neat cationic gemini surfactants alkanediyl-alpha,omega-bis(alkyldimethylammonium bromide), designated here as m-s-m, has been investigated previously in several works, but the thermotropic behavior has not been well characterized. Only for 15-s-15 and 14-s-12 have thermotropic liquid crystals (Lc) been reported. In this work, for the first time and in contrast to previous reports, we observe thermotropic Lc formation for m-2-m geminis with m = 12, 14, 16, and 18, by means of polarizing microscopy and differential scanning calorimetry (DSC). Furthermore, we investigate mixtures of m-2-m and SDS, m-2-m Br2.2SDS, which exhibit crystal-to-crystal phase transitions at lower temperature and, at high temperature, smectic Lc phases. The transition temperatures and enthalpies for Lc phases, obtained by DSC, present clear trends upon increase of the chain lengths. Combining Langmuir film experiments, possible lamellar arrangements for the different phases are tentatively discussed.
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Affiliation(s)
- Yujie Wang
- Centro de Investigação em Química, Department of Chemistry, Faculty of Sciences, University of Porto, Rua do Campo Alegre, No. 687, P-4169-007 Porto, Portugal
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48
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Sandras F, Grauby-Heywang C, Turlet JM. Spectroscopic Study of Lysopalmitoylphosphatidylcholine Newton Black Films. J Phys Chem B 2005; 109:21167-71. [PMID: 16853742 DOI: 10.1021/jp052879g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Lysopalmitoylphosphatidylcholine (LPC) black films have been studied by confocal Raman spectroscopy and their spectra analyzed and compared to their counterparts obtained from LPC in the solid state and aqueous solution. It appears that LPC is able to form stable and highly ordered black films, despite the presence of only one hydrophobic chain in this molecule. A complementary infrared study of LPC Gibbs monolayers suggests that the whole LPC polar head is perpendicular to the air/water interface. Such an orientation could explain the high order and the close packing observed in black films.
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Affiliation(s)
- Florent Sandras
- Centre de Physique Moléculaire Optique et Hertzienne, UMR 5798 du CNRS, Université Bordeaux 1, 351 cours de la libération, 33405 Talence Cedex, France
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49
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Brambilla L, Zerbi G. Local Order in Liquid n-Alkanes: Evidence from Raman Spectroscopic Study. Macromolecules 2005. [DOI: 10.1021/ma047390k] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Luigi Brambilla
- Dipartimento di Chimica, Materiali e Ingegneria Chimica “Giulio Natta”, NEMAS NanoEngineered Materials and Surfaces, Center of Excellence for Nanostructured Materials and Surfaces Engineering, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milano, Italy
| | - Giuseppe Zerbi
- Dipartimento di Chimica, Materiali e Ingegneria Chimica “Giulio Natta”, NEMAS NanoEngineered Materials and Surfaces, Center of Excellence for Nanostructured Materials and Surfaces Engineering, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milano, Italy
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50
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Fukuhara K, Mizawa T, Inoue T, Kumamoto H, Terai Y, Matsuura H, Viras K. Chain-length-dependent conformational transformation and melting behaviour of alkyl/oligo(oxyethylene)/alkyl triblock compounds: α-octyl-ω-octyloxyoligo(oxyethylene)s. Phys Chem Chem Phys 2005; 7:1457-63. [DOI: 10.1039/b414340j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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