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Grammes T, de Ligny D, Mathew D, Griebenow K, Scheffler F, Lindner F, Aichele C, Dellith J, van Wüllen L, Kamitsos EI, Brauer DS. Dispersion, ionic bonding and vibrational shifts in phospho-aluminosilicate glasses. Phys Chem Chem Phys 2024; 26:13826-13838. [PMID: 38655850 DOI: 10.1039/d4cp00685b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Understanding the relationships between structure and properties of aluminosilicate glasses is of interest in magmatic studies as well as for glass applications as mechanical or optical components. Glass properties may be tailored by the incorporation of additional elements, and here we studied the effect of phosphate incorporation on refractive index and the degree of ionic bonding in aluminosilicate glasses. The studied glasses in the system SiO2-Al2O3-Na2O-P2O5 had a metaluminous composition (Al:Na = 1) with the content of SiO2 ranging from 50 to 70 mol% and of P2O5 from 0 to 7.5 mol%. Refractive index was measured at four wavelengths from visible to near-infrared and found to decrease both with increasing P2O5 content (at the expense of NaAlO2) and with increasing SiO2 content (by substitution of SiO4 for AlO4 groups). This trend correlated with a decrease in density while, additionally, the formation of Al-O-P bonds with an SiO2-like structure may account for this change. The degree of ionic bonding, assessed via optical basicity and oxygen polarisability, decreased with increasing P2O5 and SiO2 content. Despite the complexity of the studied glasses, oxygen polarisability and optical basicity were found to follow Duffy's empirical equation for simple oxide glasses. In the high frequency infrared and Raman spectra, band shifts were observed with increasing P2O5 and SiO2 content. They indicated changing average bond strength of the glass network and showed a linear correlation with optical basicity.
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Affiliation(s)
- Thilo Grammes
- Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Lessingstr. 12 (AWZ), 07743 Jena, Germany.
| | - Dominique de Ligny
- Institute of Glass and Ceramics, Department of Materials Science and Engineering, Friedrich Alexander University Erlangen Nuremberg, Martensstr. 5, 91058 Erlangen, Germany
| | - Dintu Mathew
- Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Lessingstr. 12 (AWZ), 07743 Jena, Germany.
| | - Kristin Griebenow
- Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Lessingstr. 12 (AWZ), 07743 Jena, Germany.
| | - Franziska Scheffler
- Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Lessingstr. 12 (AWZ), 07743 Jena, Germany.
| | - Florian Lindner
- Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, 07745 Jena, Germany
| | - Claudia Aichele
- Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, 07745 Jena, Germany
| | - Jan Dellith
- Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, 07745 Jena, Germany
| | - Leo van Wüllen
- Institute of Physics, Augsburg University, Universitätsstr. 1, 86159 Augsburg, Germany
| | - Efstratios I Kamitsos
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece.
| | - Delia S Brauer
- Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Lessingstr. 12 (AWZ), 07743 Jena, Germany.
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Topper B, Möncke D, Youngman RE, Valvi C, Kamitsos EI, Varsamis CPE. Zinc borate glasses: properties, structure and modelling of the composition-dependence of borate speciation. Phys Chem Chem Phys 2023; 25:5967-5988. [PMID: 36752128 DOI: 10.1039/d2cp05517a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The short-range order of binary zinc borate glasses, xZnO-(1-x)B2O3, has been quantitatively described as a function of ZnO content over the entire glass forming range for the first time, to the best of our knowledge. Multiple spectroscopic techniques (11B NMR, Raman, infrared) reveal detailed structural information regarding borate speciation and network connectivity, and a new model for quantifying the molar fractions of short-range order units is proposed. A consistent thermal history dependence for the fraction of tetrahedral boron (N4) is well accounted for by the proposed model. The model predicts density within 0.1% of experimental values and N4 to within 1% of NMR values. The intermediate character of four-coordinated zinc in borate glasses of this series is evident by the far infrared profiles and the glass transition temperature behavior, which decreases non-monotonically with increasing ZnO content.
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Affiliation(s)
- Brian Topper
- Inamori School of Engineering at the New York State College of Ceramics, Alfred University, 1 Saxon Drive, Alfred, NY 14802, USA. .,Department of Physics & Astronomy and Center for High Technology Materials, University of New Mexico, Albuquerque, NM 87131, USA
| | - Doris Möncke
- Inamori School of Engineering at the New York State College of Ceramics, Alfred University, 1 Saxon Drive, Alfred, NY 14802, USA.
| | - Randall E Youngman
- Science and Technology Division, Corning Incorporated, Corning, New York 14831, USA
| | - Christina Valvi
- Applied Physics Laboratory, Faculty of Engineering, University of West Attica, 250 Thivon, 112 41 Egaleo, Attica, Greece.
| | - Efstratios I Kamitsos
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece
| | - Christos P E Varsamis
- Applied Physics Laboratory, Faculty of Engineering, University of West Attica, 250 Thivon, 112 41 Egaleo, Attica, Greece.
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Papadopoulos AG, Tagiara NS, Stavrou E, Li F, Yang G, Kamitsos EI. Pressure-Induced Structural Transformations and Electronic Transitions in TeO 2 Glass by Raman Spectroscopy. J Phys Chem Lett 2023; 14:387-394. [PMID: 36622290 DOI: 10.1021/acs.jpclett.2c03612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
TeO2 glass has been studied by Raman spectroscopy up to the record pressure of 70 GPa. The boson peak frequency ωb exhibits a decrease of the ∂ωb/∂P slope at 5-6 GPa and saturates above 30 GPa with a practically constant value up to 70 GPa. Experiment and theory indicate that pressures up to 20 GPa induce the transformation of single Te-O-Te bridges to double Te-O2-Te bridges, leading to a more compact structure, while Raman activity developing at higher pressures around 580 cm-1 signals the increase of Te coordination from 4- to 6-fold. Natural bond orbital analysis shows that double Te-O2-Te bridges favor the s → d transition and promote the increase of Te coordination through d2sp3 hybridization. This transition leads to the formation of TeO6 octahedra, in strict difference with crystalline TeO2 at the same pressure range, and to the development of a 3D network that freezes the medium range order.
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Affiliation(s)
- Anastasios G Papadopoulos
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 116 35Athens, Greece
| | - Nagia S Tagiara
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 116 35Athens, Greece
| | - Elissaios Stavrou
- Materials Science and Engineering Program, Guangdong Technion-Israel Institute of Technology, Shantou, Guangdong515063, China
- Department of Materials Science and Engineering, Technion-Israel Institute of Technology, Haifa32000, Israel
| | - Fei Li
- State Key Laboratory of Metastable Materials Science & Technology and Key Laboratory for Microstructural Materials Physics of Hebei Province, School of Science, Yanshan University, Qinhuangdao066004, China
| | - Guochun Yang
- State Key Laboratory of Metastable Materials Science & Technology and Key Laboratory for Microstructural Materials Physics of Hebei Province, School of Science, Yanshan University, Qinhuangdao066004, China
| | - Efstratios I Kamitsos
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 116 35Athens, Greece
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Grammes T, de Ligny D, Scheffler F, Nizamutdinova A, van Wüllen L, Kamitsos EI, Massera J, Brauer DS. Influence of Phosphate on Network Connectivity and Glass Transition in Highly Polymerized Aluminosilicate Glasses. J Phys Chem B 2022; 126:9911-9926. [DOI: 10.1021/acs.jpcb.2c06530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Thilo Grammes
- Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Fraunhoferstr. 6, 07743Jena, Germany
| | - Dominique de Ligny
- Institute of Glass and Ceramics, Department of Materials Science and Engineering, Friedrich-Alexander-Universität Erlangen-Nürnberg, Martensstr. 5, 91058Erlangen, Germany
| | - Franziska Scheffler
- Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Fraunhoferstr. 6, 07743Jena, Germany
| | - Alina Nizamutdinova
- Institute of Physics, Augsburg University, Universitätsstr. 1, 86159Augsburg, Germany
| | - Leo van Wüllen
- Institute of Physics, Augsburg University, Universitätsstr. 1, 86159Augsburg, Germany
| | - Efstratios I. Kamitsos
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635Athens, Greece
| | - Jonathan Massera
- Faculty of Medicine and Health Technology, Tampere University, Korkeakoulunkatu 3, 33720Tampere, Finland
| | - Delia S. Brauer
- Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Fraunhoferstr. 6, 07743Jena, Germany
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Varsamis CPE, Makris N, Valvi C, Kamitsos EI. Short-range structure, the role of bismuth and property-structure correlations in bismuth borate glasses. Phys Chem Chem Phys 2021; 23:10006-10020. [PMID: 33870996 DOI: 10.1039/d1cp00301a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Bismuth-containing borate glasses, xBi2O3-(1 - x)B2O3, were synthesized in the broad composition range 0.20 ≤ x ≤ 0.80 by melting in Pt crucibles and splat-quenching between two metal blocks. Infrared reflectance spectra, measured in the range 30-5000 cm-1, were transformed into absorption coefficient spectra and then deconvoluted into component bands to probe the glass structure as a function of composition. Integrated intensities of bands above 800 cm-1 were used in combination with mass and charge balance equations to quantify the short-range borate structure in terms of the molar fractions X4m, X4o, X3, X2, X1 and X0 for borate units BØ4-, BØ2O23-, BØ3, BØ2O-, BØO22- and BO33-, where Ø and O- denote bridging and non-bridging oxygen atoms. Borate tetrahedral units were found to be present in both the meta-borate, BØ4-, and ortho-borate, BØ2O23-, forms with BØ4- constituting the dominating tetrahedral species for 0.20 ≤ x ≤ 0.70. The BØ2O23- units prevail at higher Bi2O3 levels (x > 0.7), and coexist with their isomeric triangular borate species BO33- (BØ2O23- ⇌ BO33-). The present IR results for the total molar fraction of borate tetrahedral units, X4 = X4m + X4o, are in very good agreement with reported NMR results for the fraction of boron atoms in four-fold coordination, N4. Besides evaluating X4m and X4o, the present work reports also for the first time the fractions of all types of triangular borate species X3-n with n = 0, 1, 2 and 3. The IR region below 550 cm-1 was found to be dominated by the Bi-O vibrational activity in coexisting ionic (160-230 cm-1) and distorted BiO6 sites (330-365 cm-1 and 475-510 cm-1), a result reflecting the dual role of Bi2O3 as glass-modifier and glass-former oxide. The latter role dominates in glasses exceeding 60 mol% Bi2O3, and is consistent with the extended glass formation in the bismuth-borate system. The structural results were used to calculate the average number of bridging B-Ø bonds per boron center, the average Bi-O and B-O single bond energy, and the atomic packing density of the studied glasses. These properties vary approximately linearly with Bi2O3 content in the three regimes 0.2 ≤ x ≤ 0.4, 0.4 < x ≤ 0.6 and 0.6 < x ≤ 0.83, and contribute collectively to the composition dependence of glass transition temperature.
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Affiliation(s)
- C P E Varsamis
- Applied Physics Laboratory, Faculty of Engineering, University of West Attica, 250 Thivon, 112 41 Egaleo, Attica, Greece.
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Abstract
Tellurium oxide clusters (TeO2)6 were investigated through density functional theory to gain information on the structure of TeO2 glass. Among a large number of stable conformers studied, a cyclic, nonsymmetric structure was optimized without terminal Te═O double bonds. The dimer of this structure, (TeO2)12, gives calculated Raman and infrared spectra in very good agreement with the experimental ones, with its total pair distribution function being also in agreement with results of neutron and high-energy X-ray diffraction studies. The (TeO2)12 cluster consists mainly of TeO4 units connected by asymmetric and nearly symmetric Te-O-Te bridges as in γ-TeO2 and involves also edge-sharing through double-oxygen Te-O2-Te bridges as in the β-TeO2 polymorph. The optimized cluster structure is slightly unstable compared to the calculated global minimum structure, suggesting a kinetically stable product similar to its corresponding experimental TeO2 glass.
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Affiliation(s)
- Anastasios G Papadopoulos
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 116 35 Athens, Greece
| | - Nagia S Tagiara
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 116 35 Athens, Greece.,National Technical University of Athens, Zografou Campus, 15780 Athens, Greece
| | - Emmanuel D Simandiras
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 116 35 Athens, Greece
| | - Efstratios I Kamitsos
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 116 35 Athens, Greece
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Möncke D, Ali S, Jonson B, Kamitsos EI. Anion polarizabilities in oxynitride glasses. Establishing a common optical basicity scale. Phys Chem Chem Phys 2020; 22:9543-9560. [PMID: 32319995 DOI: 10.1039/c9cp06930e] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Inspired by the work of John Duffy on optical basicity of oxyfluoride glasses, we apply here the concept of optical basicity to oxynitride systems. While in the original work of Duffy and Ingram the basicity of a medium could be probed by s2 ions like Pb2+, the low energy intrinsic absorption edge of nitride-containing systems does not allow the use of such probe ions. This study uses therefore experimental data on refractive index and density of alkaline earth and rare earth containing silicate oxynitride glasses, prepared by the authors or taken from the literature. In addition, literature reports on experimental or calculated refractive index, density and polarizability data are used to compare pure nitride systems, e.g. bulk or thin film materials that are either crystalline or glassy. We compare simple and complex nitride systems with their oxygen counterparts, by calculating their optical basicity using the chemical composition as well as the established relationship between optical basicity, Λ, and electronic polarizability in oxide systems. Our results on oxynitride systems are in good agreement with Duffy's previous work on oxyfluoride glasses and indicate that the optical basicity varies for the isoelectronic anions in nitrides, oxides and fluorides (N3-:O2-:F-) of a cation Mm+ as follows: Λ(MFm) = 1/2Λ(M2Om) = 1/3Λ(M3Nm). Using this relation for CaO, for which the optical basicity was set as unity by Duffy and Ingram, one has Λ(CaF2) = 0.50, Λ(CaO) = 1.00 and Λ(Ca3N2) = 1.50. The optical basicity of complex nitrides can therefore be calculated by the same method established for oxides using the equivalent fractions and the basicity of the constituent nitrides. The relationship between nitride polarizability αN and basicity Λ(nitride) was found to be linear, with Λ(nitride) = 0.39αN- 0.14 where αN is given in Å3.
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Affiliation(s)
- Doris Möncke
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece.
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Alderman OLG, Benmore CJ, Feller S, Kamitsos EI, Simandiras ED, Liakos DG, Jesuit M, Boyd M, Packard M, Weber R. Correction to "Short-Range Disorder in TeO 2 Melt and Glass". J Phys Chem Lett 2020; 11:1377. [PMID: 32017572 DOI: 10.1021/acs.jpclett.0c00336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
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Alderman OLG, Benmore CJ, Feller S, Kamitsos EI, Simandiras ED, Liakos DG, Jesuit M, Boyd M, Packard M, Weber R. Short-Range Disorder in TeO 2 Melt and Glass. J Phys Chem Lett 2020; 11:427-431. [PMID: 31867975 DOI: 10.1021/acs.jpclett.9b03231] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
High-resolution X-ray pair distribution functions for molten and glassy TeO2 reveal coordination numbers nTeO ≈ 4. However, distinct from the known α-, β-, and γ-TeO2 polymorphs, there is considerable short-range disorder such that no clear cutoff distance between bonded and nonbonded interactions exists. We suggest that this is similar to disorder in δ-TeO2 and arises from a broad distribution of asymmetric Te-O-Te bridges, something that we observe becomes increasingly asymmetric with increasing liquid temperature. Such behavior is qualitatively consistent with existing interpretations of Raman scattering spectra, and equivalent to temperature-induced coordination number reduction, for sufficiently large cutoff radii. Therefore, TeO2 contains a distribution of local environments that are, furthermore, temperature dependent, making it distinct from the canonical single-oxide glass formers. Our results are in good agreement with high-level ab initio cluster calculations.
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Affiliation(s)
- O L G Alderman
- Materials Development, Inc. , Arlington Heights , Illinois 60004 , United States
| | - C J Benmore
- X-Ray Science Division, Advanced Photon Source , Argonne National Laboratory , Argonne , Illinois 60439 , United States
| | - S Feller
- Department of Physics , Coe College , Cedar Rapids , Iowa 52402 , United States
| | - E I Kamitsos
- National Hellenic Research Foundation , 48 Vassileos Constantinou Avenue , 11635 Athens , Greece
| | - E D Simandiras
- National Hellenic Research Foundation , 48 Vassileos Constantinou Avenue , 11635 Athens , Greece
| | - D G Liakos
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1 , 45470 Mülheim an der Ruhr , Germany
| | - M Jesuit
- Department of Physics , Coe College , Cedar Rapids , Iowa 52402 , United States
| | - M Boyd
- Department of Physics , Coe College , Cedar Rapids , Iowa 52402 , United States
| | - M Packard
- Department of Physics , Coe College , Cedar Rapids , Iowa 52402 , United States
| | - R Weber
- Materials Development, Inc. , Arlington Heights , Illinois 60004 , United States
- X-Ray Science Division, Advanced Photon Source , Argonne National Laboratory , Argonne , Illinois 60439 , United States
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Tagiara NS, Moayedi E, Kyritsis A, Wondraczek L, Kamitsos EI. Short-Range Structure, Thermal and Elastic Properties of Binary and Ternary Tellurite Glasses. J Phys Chem B 2019; 123:7905-7918. [PMID: 31433179 DOI: 10.1021/acs.jpcb.9b04617] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Glasses Al2/3O-TeO2, ZnO-TeO2 and R2/3O-ZnO-TeO2 (R = Al, B) were prepared by melting in Pt crucibles and studied for correlations between structure and thermal as well as mechanical properties, whereby the glass composition is varied to tailor the short-range speciation of tellurite, aluminate, and borate groups. The glass structure was studied by Raman and infrared spectroscopy analyses, and the measured properties include glass-transition temperature (Tg), density (ρ), and ultrasonic longitudinal (VL) and transverse (VT) velocities. In addition, atomic packing density (Cg), elastic moduli, and Poisson's ratio (σ) were evaluated from the measured properties. It was found that Al2/3O leads to cross-linked alumino-tellurite networks by strong Te-O-Al bonds, which cause a profound enhancement in Tg. The influence of ZnO and B2/3O on Tg is relatively smaller due to the weaker cross-linking effects of ZnO4 tetrahedra and of Te···O-B bonds. Short-range bonding characteristics, interatomic bonding energy differences, and atomic packing density were found to have a strong effect on VT and mostly on the VL sound velocity. The combined effects of structure and bonding are nicely expressed in the composition dependence of Poisson's ratio; it exhibits decreasing trends with Al2/3O content in the binary and ternary glasses studied here, but increasing trends with ZnO and B2/3O additions in glasses ZnO-TeO2 and B2/3O-ZnO-TeO2, respectively. The results for Poisson's ratio and atomic packing density for the studied glasses were found to fit nicely in the global σ versus Cg correlation established previously for a range of glasses not including tellurites so far. Finally, the sound velocities and Poisson's ratio of pure TeO2 glass were determined for the first time and found to differ markedly from those in the literature for TeO2 glass melted in alumina crucible; this is because the latter glass is highly doped by Al2O3 leached from the alumina crucible.
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Affiliation(s)
- N S Tagiara
- Theoretical and Physical Chemistry Institute , National Hellenic Research Foundation , 48 Vassileos Constantinou Avenue , 116 35 Athens , Greece
| | - E Moayedi
- Otto Schott Institute of Materials Research , Friedrich-Schiller-Universität Jena , Fraunhoferstrasse 6 , 07743 Jena , Germany
| | - A Kyritsis
- National Technical University of Athens , Zografou Campus , 15780 Athens , Greece
| | - L Wondraczek
- Otto Schott Institute of Materials Research , Friedrich-Schiller-Universität Jena , Fraunhoferstrasse 6 , 07743 Jena , Germany
| | - E I Kamitsos
- Theoretical and Physical Chemistry Institute , National Hellenic Research Foundation , 48 Vassileos Constantinou Avenue , 116 35 Athens , Greece
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Möncke D, Ehrt R, Palles D, Efthimiopoulos I, Kamitsos EI, Johannes M. A multi technique study of a new lithium disilicate glass-ceramic spray-coated on ZrO2 substrate for dental restoration. Biomedical Glasses 2017. [DOI: 10.1515/bglass-2017-0004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractAn alkali niobate-silicate veneer ceramic for ZrO
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12
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Möncke D, Kamitsos EI, Palles D, Limbach R, Winterstein-Beckmann A, Honma T, Yao Z, Rouxel T, Wondraczek L. Transition and post-transition metal ions in borate glasses: Borate ligand speciation, cluster formation, and their effect on glass transition and mechanical properties. J Chem Phys 2017; 145:124501. [PMID: 27782649 DOI: 10.1063/1.4962323] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A series of transition and post-transition metal ion (Mn, Cu, Zn, Pb, Bi) binary borate glasses was studied with special consideration of the cations impact on the borate structure, the cations cross-linking capacity, and more generally, structure-property correlations. Infrared (IR) and Raman spectroscopies were used for the structural characterization. These complementary techniques are sensitive to the short-range order as in the differentiation of tetrahedral and trigonal borate units or regarding the number of non-bridging oxygen ions per unit. Moreover, vibrational spectroscopy is also sensitive to the intermediate-range order and to the presence of superstructural units, such as rings and chains, or the combination of rings. In order to clarify band assignments for the various borate entities, examples are given from pure vitreous B2O3 to meta-, pyro-, ortho-, and even overmodified borate glass compositions. For binary metaborate glasses, the impact of the modifier cation on the borate speciation is shown. High field strength cations such as Zn2+ enhance the disproportionation of metaborate to polyborate and pyroborate units. Pb2+ and Bi3+ induce cluster formation, resulting in PbOn- and BiOn-pseudophases. Both lead and bismuth borate glasses show also a tendency to stabilize very large superstructural units in the form of diborate polyanions. Far-IR spectra reflect on the bonding states of modifier cations in glasses. The frequency of the measured cation-site vibration band was used to obtain the average force constant for the metal-oxygen bonding, FM-O. A linear correlation between glass transition temperature (Tg) and FM-O was shown for the metaborate glass series. The mechanical properties of the glasses also correlate with the force constant FM-O, though for cations of similar force constant the fraction of tetrahedral borate units (N4) strongly affects the thermal and mechanical properties. For paramagnetic Cu- and Mn-borate glasses, N4 was determined from the IR spectra after deducing the relative absorption coefficient of boron tetrahedral versus boron trigonal units, α = α4/α3, using NMR literature data of the diamagnetic glasses.
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Affiliation(s)
- D Möncke
- Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Fraunhoferstraße 6, 07743 Jena, Germany
| | - E I Kamitsos
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece
| | - D Palles
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece
| | - R Limbach
- Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Fraunhoferstraße 6, 07743 Jena, Germany
| | - A Winterstein-Beckmann
- Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Fraunhoferstraße 6, 07743 Jena, Germany
| | - T Honma
- Department of Materials Science and Technology, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Japan
| | - Z Yao
- Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Fraunhoferstraße 6, 07743 Jena, Germany
| | - T Rouxel
- Institute of Physics, UMR UR1-CNRS 6251, University of Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| | - L Wondraczek
- Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Fraunhoferstraße 6, 07743 Jena, Germany
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Kontos AG, Kaltzoglou A, Siranidi E, Palles D, Angeli GK, Arfanis MK, Psycharis V, Raptis YS, Kamitsos EI, Trikalitis PN, Stoumpos CC, Kanatzidis MG, Falaras P. Structural Stability, Vibrational Properties, and Photoluminescence in CsSnI 3 Perovskite upon the Addition of SnF 2. Inorg Chem 2016; 56:84-91. [PMID: 28043139 DOI: 10.1021/acs.inorgchem.6b02318] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The CsSnI3 perovskite and the corresponding SnF2-containing material with nominal composition CsSnI2.95F0.05 were synthesized by solid-state reactions and structurally characterized by powder X-ray diffraction. Both materials undergo rapid phase transformation upon exposure to air from the black orthorhombic phase (B-γ-CsSnI3) to the yellow orthorhombic phase (Y-CsSnI3), followed by irreversible oxidation into Cs2SnI6 within several hours. The phase transition occurs at a significantly lower rate in the SnF2-containing material rather than in the pure perovskite. The high hole-carrier concentration of the materials prohibits the detection of Raman signals for B-γ-CsSnI3 and induces a very strong plasmonic reflectance in the far-IR. In contrast, far-IR phonon bands and a rich Raman spectrum are observed for the Y-CsSnI3 modification below 140 cm-1 with weak frequency shift gradients versus temperatures between -95 and +170 °C. Above 170 °C, the signal is lost due to B-α-CsSnI3 re-formation. The photoluminescence spectra exhibit residual blue shifts and broadening as a sign of structural transformation initiation.
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Affiliation(s)
- Athanassios G Kontos
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos , Athens 15310, Greece
| | - Andreas Kaltzoglou
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos , Athens 15310, Greece
| | - Eirini Siranidi
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos , Athens 15310, Greece
| | - Dimitrios Palles
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation , Athens 11635, Greece
| | - Giasemi K Angeli
- Department of Chemistry, University of Crete , Heraklion 71003, Greece
| | - Michalis K Arfanis
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos , Athens 15310, Greece
| | - Vassilis Psycharis
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos , Athens 15310, Greece
| | - Yannis S Raptis
- Faculty of Applied Sciences, National Technical University of Athens , Athens 15780, Greece
| | - Efstratios I Kamitsos
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation , Athens 11635, Greece
| | | | | | - Mercouri G Kanatzidis
- Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States
| | - Polycarpos Falaras
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos , Athens 15310, Greece
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Winterstein-Beckmann A, Möncke D, Palles D, Kamitsos EI, Wondraczek L. Structure and Properties of Orthoborate Glasses in the Eu2O3–(Sr,Eu)O–B2O3 Quaternary. J Phys Chem B 2015; 119:3259-72. [DOI: 10.1021/jp5120465] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Anja Winterstein-Beckmann
- Otto
Schott Institute of Materials Research, University of Jena, Fraunhoferstrasse 6, 07743 Jena, Germany
| | - Doris Möncke
- Otto
Schott Institute of Materials Research, University of Jena, Fraunhoferstrasse 6, 07743 Jena, Germany
| | - Dimitrios Palles
- Theoretical
and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece
| | - Efstratios I. Kamitsos
- Theoretical
and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece
| | - Lothar Wondraczek
- Otto
Schott Institute of Materials Research, University of Jena, Fraunhoferstrasse 6, 07743 Jena, Germany
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Möncke D, Sirotkin S, Stavrou E, Kamitsos EI, Wondraczek L. Partitioning and structural role of Mn and Fe ions in ionic sulfophosphate glasses. J Chem Phys 2014; 141:224509. [DOI: 10.1063/1.4903191] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Doris Möncke
- Otto-Schott-Institute of Materials Research, Friedrich-Schiller-University Jena, Fraunhoferstr. 6, 07743 Jena, Germany
| | - Sergey Sirotkin
- Institut des Sciences Moléculaires - CNRS UMR 5255, Université de Bordeaux, 33405 Talence, France
| | - Elissaios Stavrou
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constaniou Ave., 116 35 Athens, Greece
| | - Efstratios I. Kamitsos
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constaniou Ave., 116 35 Athens, Greece
| | - Lothar Wondraczek
- Otto-Schott-Institute of Materials Research, Friedrich-Schiller-University Jena, Fraunhoferstr. 6, 07743 Jena, Germany
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Ioannou EF, Mountrichas G, Pispas S, Kamitsos EI, Floudas G. Lithium Ion Induced Nanophase Ordering and Ion Mobility in Ionic Block Copolymers. Macromolecules 2008. [DOI: 10.1021/ma8008542] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Eirini F. Ioannou
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vass. Constantinou Ave., 116 35, Athens, Greece
| | - Grigoris Mountrichas
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vass. Constantinou Ave., 116 35, Athens, Greece
| | - Stergios Pispas
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vass. Constantinou Ave., 116 35, Athens, Greece
| | - Efstratios I. Kamitsos
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vass. Constantinou Ave., 116 35, Athens, Greece
| | - George Floudas
- Department of Physics, University of Ioannina, P.O. Box 1186, 451 10, Ioannina, Greece, and Foundation for Research and Technology−Hellas, Biomedical Research Institute (FORTH-BRI)
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17
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Dussauze M, Giannoudakos A, Velli L, Varsamis CPE, Kompitsas M, Kamitsos EI. Structure and optical properties of amorphous lead-germanate films developed by pulsed-laser deposition. J Chem Phys 2007; 127:034704. [PMID: 17655452 DOI: 10.1063/1.2752503] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Lead-germanate materials are attractive systems for photonics applications. In this context, amorphous lead-germanate films were grown by pulsed-laser deposition at different substrate temperatures and oxygen pressures using a glassy target of composition 0.4PbO-0.6GeO(2). Optical and infrared measurements showed that the substrate temperature has a strong influence on the optical quality and stability of the deposited films. An accurate characterization of films was achieved by comparing experimental and simulated transmittance spectra in the infrared, and allowed to probe the structural evolution and variations in composition as a function of oxygen pressure. The results showed that the difference in reactivity of lead and germanium toward oxygen in the laser-produced plasma allows for composition adjustments in the lead-germanate films by varying the oxygen pressure in the deposition chamber.
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Affiliation(s)
- M Dussauze
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece
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Abstract
The structural aspects of xCs2O-(1-x)B2O3 glasses have been investigated by molecular dynamics as functions of Cs2O content (x=0.2, 0.3, and 0.4) and temperature (T=300 and 1250 K). The tetrahedral (BØ4-) and triangular (BØ3,BØ2O-, and BØO2 (2-)) short-range order borate units were found to be the structure-building entities of the simulated glasses [Ø=bridging oxygen (BO) and O-=nonbridging oxygen (NBO) atom]. The increase of Cs2O content results in the progressive increase of the NBO-containing triangle population at the expense of the BO4- tetrahedral units. The same effect is caused by temperature increase at a fixed Cs2O content, and this was associated with the "fragile" characteristics of alkali borate glasses. A comparison of simulated Cs and Li borates showed very similar structures at x=0.2, but dissimilar ones when the alkali content exceeds this composition. In particular, for x>0.2 Cs borates exhibit a preference for NBO formation relative to Li borates. Differences in the microstructure of sites hosting Cs ions were found, and this permits their classification into bridging (b type) and nonbridging type (nb type) of sites. b-type sites consist exclusively of BO atoms, while both BO and NBO atoms participate in nb-type sites. These differences in Cs-site local bonding characteristics were found to be reflected on the Cs-O(site) vibration frequencies. Also, the computed Cs-O vibrational responses for simulated Cs borates were found to compare well with experimental far-infrared spectra.
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Affiliation(s)
- Alice Vegiri
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, Athens 11635, Greece
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Benaki DC, Aggeli A, Chryssikos GD, Yiannopoulos YD, Kamitsos EI, Brumley E, Case ST, Boden N, Hamodrakas SJ. Laser-Raman and FT-IR spectroscopic studies of peptide-analogues of silkmoth chorion protein segments. Int J Biol Macromol 1998; 23:49-59. [PMID: 9644596 DOI: 10.1016/s0141-8130(98)00032-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Silkmoth chorion, the proteinaceous major component of the eggshell, with extraordinary mechanical and physiological properties, consists of a complex set of proteins, which have a tripartite structure: a central, evolutionarily conserved, domain and two more variable 'arms'. Peptide-analogues of silkmoth chorion protein central domain segments have been synthesized. Laser-Raman and infrared spectroscopic studies suggest the preponderance of antiparallel beta-pleated sheet structure for these peptides, both in solution and in the solid state.
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Affiliation(s)
- D C Benaki
- Department of Biology, University of Athens, Greece
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20
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Kamitsos EI, Yiannopoulos YD, Jain H, Huang WC. Far-infrared spectra of alkali germanate glasses and correlation with electrical conductivity. Phys Rev B Condens Matter 1996; 54:9775-9783. [PMID: 9984711 DOI: 10.1103/physrevb.54.9775] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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21
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Kamitsos EI. Reply to "Comment on 'Infrared-reflectance spectra of heat-treated, sol-gel-derived silica' ". Phys Rev B Condens Matter 1996; 53:14659-14662. [PMID: 9983268 DOI: 10.1103/physrevb.53.14659] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Voyiatzis G, Petekidis G, Vlassopoulos D, Kamitsos EI, Bruggeman A. Molecular Orientation in Polyester Films Using Polarized Laser Raman and Fourier Transform Infrared Spectroscopies and X-Ray Diffraction. Macromolecules 1996. [DOI: 10.1021/ma951199g] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- George Voyiatzis
- Foundation for Research & Technology-Hellas, Institute of Chemical Engineering and High Temperature Chemical Processes, P.O. Box 1414, 26500 Patras, Greece
| | - Giorgos Petekidis
- Foundation for Research & Technology-Hellas, Institute of Electronic Structure & Laser, P.O. Box 1527, 71110 Heraklion, Crete, Greece
| | - Dimitris Vlassopoulos
- Foundation for Research & Technology-Hellas, Institute of Electronic Structure & Laser, P.O. Box 1527, 71110 Heraklion, Crete, Greece
| | - Efstratios I. Kamitsos
- National Hellenic Research Foundation, Institute of Theoretical and Physical Chemistry, 48 Vas. Constantinou Avenue, 11635 Athens, Greece
| | - Albert Bruggeman
- TNO Plastics and Rubber Research Institute, P.O. Box 6031, 2600 JA Delft, The Netherlands
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Orfanidou CC, Hamodrakas SJ, Chryssikos GD, Kamitsos EI, Wellman SE, Case ST. Spectroscopic studies of Manduca sexta and Sesamia nonagrioides chorion protein structure. Int J Biol Macromol 1995; 17:93-8. [PMID: 7547721 DOI: 10.1016/0141-8130(95)93523-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The secondary structure of Manduca sexta and Sesamia nonagrioides chorion proteins has been studied in intact chorions using laser-Raman and Fourier transform infra-red (FTIR) spectroscopy and in a solution containing extracted and reassembled chorion proteins using circular dichroism (CD) spectroscopy. Laser-Raman and IR spectra suggest the predominance of antiparallel beta-pleated sheet structure in intact chorion proteins of both Lepidoptera species. The bands at 1673, 1674 cm-1 (amide I) and 1234-1238 cm-1 (amide III) in the laser-Raman spectra can best be interpreted as resulting from abundant antiparallel beta-pleated sheet structure. Analysis of the amide I band suggests that chorion proteins consist of 60-70% antiparallel beta-pleated sheet and 30-40% beta-turns. Supporting evidence for the prevalence of antiparallel beta-pleated sheet in chorion proteins was supplied using FTIR spectroscopy by the observation of a very intense absorption band at 1635 cm-1 (amide I) and of a weak band at 1530, 1525 cm-1 (amide II) from chorions of both species. Surprisingly, analysis of the CD spectra of extracted and reassembled chorion proteins suggests that, in solution, they retain a regular secondary structure most probably dominated by beta-pleated sheet. We therefore suggest that the prominent regular beta-sheet structure of chorion proteins may exist in solution and dictate the aggregation and polymerization process in vivo.
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Affiliation(s)
- C C Orfanidou
- Department of Biochemistry, Cell and Molecular Biology and Genetics, University of Athens, Greece
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Kamitsos EI, Patsis AP, Kordas G. Infrared-reflectance spectra of heat-treated sol-gel-derived silica. Phys Rev B Condens Matter 1993; 48:12499-12505. [PMID: 10007617 DOI: 10.1103/physrevb.48.12499] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Wellman SE, Hamodrakas SJ, Kamitsos EI, Case ST. Secondary structure of synthetic peptides derived from the repeating unit of a giant secretory protein from Chironomus tentans. Biochim Biophys Acta 1992; 1121:279-85. [PMID: 1627605 DOI: 10.1016/0167-4838(92)90157-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The secretory proteins of Chironomus tentans larvae, which are used to construct underwater feeding and pupation tubes, assemble into complexes in vitro. Members of a family of 1000 kDa proteins, the spIs, appear to form the fibrous backbone of the assembled complexes. The spIs consist of a core of tandemly repeating units of 60 to 90 amino acids that can be subdivided into two regions: the subrepeat region, made up of short internal repeats, and the constant region, which lacks simple subrepeats. We have synthesized peptides representative of the constant and subrepeat regions of one of the spIs, and have examined their secondary structure using Fourier transform IR and CD spectroscopy. The IR spectrum of the constant peptide indicates that this peptide has alpha-helical regions and beta-turns. The CD spectrum confirms this. The IR spectrum of the subrepeat peptide is similar to that of the poly(Gly)II helix, and also may indicate the presence of beta-turns. The CD spectrum is consistent with this helical structure. Extrapolation of these results to intact spIs is in agreement with secondary structure prediction and modeling studies. Our results indicate that the alpha-helices and poly(Gly)II-like helices are not arranged as coiled-coils, which are often found in fibrous proteins. We suggest that these structural elements may be in an unusual arrangement in the spIs, organized as alternating alpha-helices and poly(Gly)II or collagen-like helices, interspersed with beta-turns.
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Affiliation(s)
- S E Wellman
- Department of Biochemistry, University of Mississippi Medical Center, Jackson 39216-4505
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Hamodrakas SJ, Kamitsos EI, Papadopoulou PG. Laser-Raman and infrared spectroscopic studies of protein conformation in the eggshell of the fish Salmo gairdneri. Biochim Biophys Acta 1987; 913:163-9. [PMID: 3593737 DOI: 10.1016/0167-4838(87)90326-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Laser-Raman and infrared spectroscopic studies reveal abundant beta-pleated sheet conformation in the eggshell proteins of the fish Salmo gairdneri. This secondary structure is the underlying molecular conformation, dictating the formation of the helicoidal architecture of the eggshell. Disulphide bonds crosslink the eggshell proteins of the fertilized eggs and are apparently found in g-g-g (gauche-gauche-gauche), g-g-t (gauche-gauche-trans) and t-g-t (trans-gauche-trans) conformation. There is no evidence for the existence of free sulphydryls. The tyrosines appear to act as hydrogen-bond acceptors, whereas the aromatic residues phenylalanine and tryptophan are also eggshell protein constituents.
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Kamitsos EI, Risen WM. Raman studies in CuTCNQ: Resonance Raman spectral observations and calculations for TCNQ ion radicals. J Chem Phys 1983. [DOI: 10.1063/1.445769] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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