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Keywords = 3D glass diagram

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20 pages, 11103 KB  
Data Descriptor
VitralColor-12: A Synthetic Twelve-Color Segmentation Dataset from GPT-Generated Stained-Glass Images
by Martín Montes Rivera, Carlos Guerrero-Mendez, Daniela Lopez-Betancur, Tonatiuh Saucedo-Anaya, Manuel Sánchez-Cárdenas and Salvador Gómez-Jiménez
Data 2025, 10(10), 165; https://doi.org/10.3390/data10100165 - 18 Oct 2025
Viewed by 696
Abstract
The segmentation and classification of color are crucial stages in image processing, computer vision, and pattern recognition, as they significantly impact the results. The diverse, hand-labeled datasets in the literature are applied for monochromatic or color segmentation in specific domains. On the other [...] Read more.
The segmentation and classification of color are crucial stages in image processing, computer vision, and pattern recognition, as they significantly impact the results. The diverse, hand-labeled datasets in the literature are applied for monochromatic or color segmentation in specific domains. On the other hand, synthetic datasets are generated using statistics, artificial intelligence algorithms, or generative artificial intelligence (AI). This last one includes Large Language Models (LLMs), Generative Adversarial Neural Networks (GANs), and Variational Autoencoders (VAEs), among others. In this work, we propose VitralColor-12, a synthetic dataset for color classification and segmentation, comprising twelve colors: black, blue, brown, cyan, gray, green, orange, pink, purple, red, white, and yellow. VitralColor-12 addresses the limitations of color segmentation and classification datasets by leveraging the capabilities of LLMs, including adaptability, variability, copyright-free content, and lower-cost data—properties that are desirable in image datasets. VitralColor-12 includes pixel-level classification and segmentation maps. This makes the dataset broadly applicable and highly variable for a range of computer vision applications. VitralColor-12 utilizes GPT-5 and DALL·E 3 for generating stained-glass images. These images simplify the annotation process, since stained-glass images have isolated colors with distinct boundaries within the steel structure, which provide easy regions to label with a single color per region. Once we obtain the images, we use at least one hand-labeled centroid per color to automatically cluster all pixels based on Euclidean distance and morphological operations, including erosion and dilation. This process enables us to automatically label a classification dataset and generate segmentation maps. Our dataset comprises 910 images, organized into 70 generated images and 12 pixel segmentation maps—one for each color—which include 9,509,524 labeled pixels, 1,794,758 of which are unique. These annotated pixels are represented by RGB, HSL, CIELAB, and YCbCr values, enabling a detailed color analysis. Moreover, VitralColor-12 offers features that address gaps in public resources such as violin diagrams with the frequency of colors across images, histograms of channels per color, 3D color maps, descriptive statistics, and standardized metrics, such as ΔE76, ΔE94, and CIELAB Chromacity, which prove the distribution, applicability, and realistic perceptual structures, including warm, neutral, and cold colors, as well as the high contrast between black and white colors, offering meaningful perceptual clusters, reinforcing its utility for color segmentation and classification. Full article
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19 pages, 7104 KB  
Article
Athermal and Apochromatic Design of Equivalent Two-Component Optical System in 3D Glass Diagram
by Yingjun Ma, Hongtao Yang, Weining Chen, Jianwei Peng, Huinan Guo and Guangdong Zhang
Photonics 2024, 11(8), 719; https://doi.org/10.3390/photonics11080719 - 31 Jul 2024
Cited by 4 | Viewed by 1619
Abstract
In the athermal and apochromatic design of optical systems, the distribution of lens’ optical powers and the selection of optical glass and structural materials are crucial. In this paper, an athermal and apochromatic design method is proposed for optical systems with a long [...] Read more.
In the athermal and apochromatic design of optical systems, the distribution of lens’ optical powers and the selection of optical glass and structural materials are crucial. In this paper, an athermal and apochromatic design method is proposed for optical systems with a long focal length, large relative aperture, and wide spectrum. Firstly, a complex optical system composed of multiple lenses is equivalent to a two-component, single-lens system consisting of a replacement and an equivalent lens group. The optical glass for the replacement lens group is selected based on weight and the principle of material replacement in the 3D glass diagram, thus achieving an athermal and apochromatic design. Secondly, an athermal and apochromatic optical system with a focal length of 130 mm, an F-number of 2.0, a spectral range of 480 nm~800 nm, a field of view angle of 22°, and an operating temperature of −40 °C~+60 °C is designed. The modulation transfer function (MTF) at each field of view is greater than 0.6 at 50 lp/mm in the −40 °C~+60 °C temperature range, and the secondary spectrum aberration is 0.0056 mm, which is within the focal depth range of the optical system. Full article
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6 pages, 825 KB  
Proceeding Paper
Determination of Critical Storage Conditions for Spray-Dried Habanero Pepper (Capsicum chinense) Extracts by Coupling Water Adsorption Isotherms and Glass Transition Temperature
by Ubaldo Richard Marín Castro, Fernando Cansino Jácome, José Arturo Olguín-Rojas, Guadalupe del Carmen Rodríguez-Jimenes, María Teresa González Arnao, Enrique Flores Andrade and Martha Paola Rascón Díaz
Biol. Life Sci. Forum 2023, 26(1), 97; https://doi.org/10.3390/Foods2023-151 - 17 Oct 2023
Viewed by 1054
Abstract
This study aimed to determine storage conditions for microparticles containing habanero pepper extracts with maltodextrin (MD) and a 95:5 w/w mixture with precipitated silica (MDSP) as wall materials. State diagrams (SD) using water adsorption isotherms and glass transition temperatures were created. [...] Read more.
This study aimed to determine storage conditions for microparticles containing habanero pepper extracts with maltodextrin (MD) and a 95:5 w/w mixture with precipitated silica (MDSP) as wall materials. State diagrams (SD) using water adsorption isotherms and glass transition temperatures were created. Monolayer values were 6.17 g (MD) and 6.76 g (MDSP) of water/100 g d.s. Critical water activity values (awC) were 0.49 for MD and 0.41 for MDSP. When stored at aw > awC, both samples underwent physical transformations, with significant color changes (ΔE > 8). Conversely, storage below awC resulted in minimal changes (ΔE < 4), consistent with the SD. Full article
(This article belongs to the Proceedings of The 4th International Electronic Conference on Foods)
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21 pages, 39602 KB  
Article
Developing Techniques for Closed-Loop-Recycling Soda-Lime Glass Fines through Robotic Deposition
by Maria Sparre-Petersen and Simona Hnídková
Arts 2023, 12(4), 166; https://doi.org/10.3390/arts12040166 - 27 Jul 2023
Viewed by 2917
Abstract
Glass is made from sand—a finite resource. Hence, there is a need to maintain glass in the industrial cycle as described in the Ellen MacArthur Foundation’s circular-economy diagram. This research project examines the reallocation of material resources in the form of waste glass [...] Read more.
Glass is made from sand—a finite resource. Hence, there is a need to maintain glass in the industrial cycle as described in the Ellen MacArthur Foundation’s circular-economy diagram. This research project examines the reallocation of material resources in the form of waste glass fines from the industrial recycling process for soda-lime glass. According to the plant manager of Reiling Glasrecycling Danmark ApS, the fines are currently sold to be used for insulation. Although this process prolongs the lifespan of the fines before they become landfill waste, a closed-loop circular option would be preferable. In order to establish a closed-loop circular model for waste glass fines, this research investigates their material and aesthetic qualities and proposes a strategy for maintaining the fines in the closed loop cycle together with the soda-lime glass. The fines are manipulated through robotic deposition and formed into 3D geometries. To expand the aesthetic applications for the material, an investigation is conducted by combining 3D geometries with the traditional glassmaking techniques of glassblowing and casting. The research contributes knowledge of the materials’ technical qualities including printability, durability and workability of the 3D prints combined with cast or blown recycled container glass as well as with blown waste glass fines. Technical obstacles are revealed and alternative routes for further explorations are suggested. Finally, the performative and aesthetic qualities of the results are discussed, while artistic applications for recycled soda-lime glass fines remain to be explored in future research. Full article
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13 pages, 3395 KB  
Article
Spectroscopic Properties of Pr3+, Tm3+, and Ho3+ in Germanate-Based Glass Systems Modified by TiO2
by Marta Kuwik, Karolina Kowalska, Joanna Pisarska and Wojciech A. Pisarski
Materials 2023, 16(1), 61; https://doi.org/10.3390/ma16010061 - 21 Dec 2022
Cited by 7 | Viewed by 2218
Abstract
In this paper, the effect of the GeO2:TiO2 molar ratio in glass composition on the spectroscopic properties of germanate glasses was systematically investigated. The visible luminescence bands associated with characteristic 1D23H4 (red), 5S [...] Read more.
In this paper, the effect of the GeO2:TiO2 molar ratio in glass composition on the spectroscopic properties of germanate glasses was systematically investigated. The visible luminescence bands associated with characteristic 1D23H4 (red), 5S2, 5F45I8 (green), and 1D23F4 (blue) transitions of Pr3+, Ho3+, and Tm3+ ions in systems modified by TiO2 were well observed, respectively. It was found that the luminescence intensity of glasses containing Pr3+ and Ho3+ ions increases, whereas, for Tm3+-doped systems, luminescence quenching with increasing content of TiO2 was observed. Based on Commission Internationale de I’Eclairage (CIE) chromaticity coordinates (x, y) analysis, it was demonstrated that the value of chromaticity coordinates for all glasses depends on the GeO2:TiO2 molar ratio. The addition of TiO2 to system compositions doped with Tm3+ ions shifts the (x, y) to the center of the CIE diagram. However, chromaticity coordinates evaluated for glasses containing Pr3+ ions move to a purer red color. Our results confirm that the spectroscopic properties of the studied glasses strongly depend on TiO2 content. Moreover, it can be stated that germanate-based glass systems modified by TiO2 can be used for optoelectronics in RGB technology as red (Pr3+), green (Ho3+), and blue (Tm3+) emitters. Full article
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16 pages, 9363 KB  
Review
From Chaos to Ordering: New Studies in the Shannon Entropy of 2D Patterns
by Irina Legchenkova, Mark Frenkel, Nir Shvalb, Shraga Shoval, Oleg V. Gendelman and Edward Bormashenko
Entropy 2022, 24(6), 802; https://doi.org/10.3390/e24060802 - 8 Jun 2022
Cited by 5 | Viewed by 4198
Abstract
Properties of the Voronoi tessellations arising from random 2D distribution points are reported. We applied an iterative procedure to the Voronoi diagrams generated by a set of points randomly placed on the plane. The procedure implied dividing the edges of Voronoi cells into [...] Read more.
Properties of the Voronoi tessellations arising from random 2D distribution points are reported. We applied an iterative procedure to the Voronoi diagrams generated by a set of points randomly placed on the plane. The procedure implied dividing the edges of Voronoi cells into equal or random parts. The dividing points were then used to construct the following Voronoi diagram. Repeating this procedure led to a surprising effect of the positional ordering of Voronoi cells, reminiscent of the formation of lamellae and spherulites in linear semi-crystalline polymers and metallic glasses. Thus, we can conclude that by applying even a simple set of rules to a random set of seeds, we can introduce order into an initially disordered system. At the same time, the Shannon (Voronoi) entropy showed a tendency to attain values that are typical for completely random patterns; thus, the Shannon (Voronoi) entropy does not distinguish the short-range ordering. The Shannon entropy and the continuous measure of symmetry of the patterns demonstrated the distinct asymptotic behavior, while approaching the close saturation values with the increase in the number of iteration steps. The Shannon entropy grew with the number of iterations, whereas the continuous measure of symmetry of the same patterns demonstrated the opposite asymptotic behavior. The Shannon (Voronoi) entropy is not an unambiguous measure of order in the 2D patterns. The more symmetrical patterns may demonstrate the higher values of the Shannon entropy. Full article
(This article belongs to the Section Entropy Reviews)
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16 pages, 3926 KB  
Article
A Hot-Melt Extrusion Risk Assessment Classification System for Amorphous Solid Dispersion Formulation Development
by Samuel O. Kyeremateng, Kristin Voges, Stefanie Dohrn, Ekaterina Sobich, Ute Lander, Stefan Weber, David Gessner, Rachel C. Evans and Matthias Degenhardt
Pharmaceutics 2022, 14(5), 1044; https://doi.org/10.3390/pharmaceutics14051044 - 12 May 2022
Cited by 23 | Viewed by 5799
Abstract
Several literature publications have described the potential application of active pharmaceutical ingredient (API)–polymer phase diagrams to identify appropriate temperature ranges for processing amorphous solid dispersion (ASD) formulations via the hot-melt extrusion (HME) technique. However, systematic investigations and reliable applications of the phase diagram [...] Read more.
Several literature publications have described the potential application of active pharmaceutical ingredient (API)–polymer phase diagrams to identify appropriate temperature ranges for processing amorphous solid dispersion (ASD) formulations via the hot-melt extrusion (HME) technique. However, systematic investigations and reliable applications of the phase diagram as a risk assessment tool for HME are non-existent. Accordingly, within AbbVie, an HME risk classification system (HCS) based on API–polymer phase diagrams has been developed as a material-sparing tool for the early risk assessment of especially high melting temperature APIs, which are typically considered unsuitable for HME. The essence of the HCS is to provide an API risk categorization framework for the development of ASDs via the HME process. The proposed classification system is based on the recognition that the manufacture of crystal-free ASD using the HME process fundamentally depends on the ability of the melt temperature to reach the API’s thermodynamic solubility temperature or above. Furthermore, we explored the API–polymer phase diagram as a simple tool for process design space selection pertaining to API or polymer thermal degradation regions and glass transition temperature-related dissolution kinetics limitations. Application of the HCS was demonstrated via HME experiments with two high melting temperature APIs, sulfamerazine and telmisartan, with the polymers Copovidone and Soluplus. Analysis of the resulting ASDs in terms of the residual crystallinity and degradation showed excellent agreement with the preassigned HCS class. Within AbbVie, the HCS concept has been successfully applied to more than 60 different APIs over the last 8 years as a robust validated risk assessment and quality-by-design (QbD) tool for the development of HME ASDs. Full article
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13 pages, 754 KB  
Article
The Water Polymorphism and the Liquid–Liquid Transition from Transport Data
by Francesco Mallamace, Domenico Mallamace, Giuseppe Mensitieri, Sow-Hsin Chen, Paola Lanzafame and Georgia Papanikolaou
Physchem 2021, 1(2), 202-214; https://doi.org/10.3390/physchem1020014 - 25 Aug 2021
Cited by 5 | Viewed by 4047
Abstract
NMR spectroscopic literature data are used, in a wide temperature-pressure range (180–350 K and 0.1–400 MPa), to study the water polymorphism and the validity of the liquid–liquid transition (LLT) hypothesis. We have considered the self-diffusion coefficient DS and the reorientational correlation time [...] Read more.
NMR spectroscopic literature data are used, in a wide temperature-pressure range (180–350 K and 0.1–400 MPa), to study the water polymorphism and the validity of the liquid–liquid transition (LLT) hypothesis. We have considered the self-diffusion coefficient DS and the reorientational correlation time τθ (obtained from spin-lattice T1 relaxation times), measured, respectively, in bulk and emulsion liquid water from the stable to well inside the metastable supercooled region. As an effect of the hydrogen bond (HB) networking, the isobars of both these transport functions evolve with T by changing by several orders of magnitude, whereas their pressure dependence become more and more pronounced at lower temperatures. Both these transport functions were then studied according to the Adam–Gibbs model, typical of glass forming liquids, obtaining the water configurational entropy and the corresponding specific heat contribution. The comparison of the evaluated CP,conf isobars with the experimentally measured water specific heat reveals the full consistency of this analysis. In particular, the observed CP,conf maxima and its diverging behaviors clearly reveals the presence of the LLT and with a reasonable approximation the liquid–liquid critical point (LLCP) locus in the phase diagram. Full article
(This article belongs to the Special Issue Physical Chemistry Perspectives for the New Decade)
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16 pages, 4038 KB  
Article
Three-Dimensional High Spatial Localization of Efficient Resonant Energy Transfer from Laser-Assisted Precipitated Silver Clusters to Trivalent Europium Ions
by Yannick Petit, Gustavo Galleani, Guillaume Raffy, Jean-Charles Desmoulin, Véronique Jubéra, André Del Guerzo, Andrea Simone Stucchi de Camargo, Lionel Canioni and Thierry Cardinal
Crystals 2021, 11(2), 148; https://doi.org/10.3390/cryst11020148 - 1 Feb 2021
Cited by 9 | Viewed by 3222
Abstract
We report on the 3D precipitation, using a direct laser writing approach, of highly fluorescent silver clusters in a Eu3+-doped silver-containing zinc phosphate glass. Micro-spectroscopy of fluorescence emission shows the ability to continuously adjust the local tri-chromatic coordinates in the CIE [...] Read more.
We report on the 3D precipitation, using a direct laser writing approach, of highly fluorescent silver clusters in a Eu3+-doped silver-containing zinc phosphate glass. Micro-spectroscopy of fluorescence emission shows the ability to continuously adjust the local tri-chromatic coordinates in the CIE (Commission Internationale de l’Éclairage) chromaticity diagram between red and white colors, thanks to the laser-deposited dose and resulting tunable combination of emissions from Eu3+ and silver clusters. Moreover, continuous-wave and time-resolved FAST-FLIM spectroscopies showed a significant enhancement of the fluorescence emission of Eu3+ ions while being co-located with UV-excited laser-inscribed silver clusters. These results demonstrate the ability to perform efficient resonant non-radiative energy transfer from excited silver clusters to Eu3+, allowing such energy transfer to be highly localized on demand thanks to laser inscription. Such results open the route to 3D printing of the rare earth ions emission in glass. Full article
(This article belongs to the Special Issue Laser-Induced Crystallization)
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29 pages, 10348 KB  
Article
Phase-Field Fracture Modelling of Thin Monolithic and Laminated Glass Plates under Quasi-Static Bending
by Jaroslav Schmidt, Alena Zemanová, Jan Zeman and Michal Šejnoha
Materials 2020, 13(22), 5153; https://doi.org/10.3390/ma13225153 - 16 Nov 2020
Cited by 13 | Viewed by 3527
Abstract
A phase-field description of brittle fracture is employed in the reported four-point bending analyses of monolithic and laminated glass plates. Our aims are: (i) to compare different phase-field fracture formulations applied to thin glass plates, (ii) to assess the consequences of the dimensional [...] Read more.
A phase-field description of brittle fracture is employed in the reported four-point bending analyses of monolithic and laminated glass plates. Our aims are: (i) to compare different phase-field fracture formulations applied to thin glass plates, (ii) to assess the consequences of the dimensional reduction of the problem and mesh density and refinement, and (iii) to validate for quasi-static loading the time-/temperature-dependent material properties we derived recently for two commonly used polymer foils made of polyvinyl butyral or ethylene-vinyl acetate. As the nonlinear response prior to fracture, typical of the widely used Bourdin–Francfort–Marigo model, can lead to a significant overestimation of the response of thin plates under bending, the numerical study investigates two additional phase-field fracture models providing the linear elastic phase of the stress-strain diagram. The typical values of the critical fracture energy and tensile strength of glass lead to a phase-field length-scale parameter that is challenging to resolve in the numerical simulations. Therefore, we show how to determine the fracture energy concerning the applied dimensional reduction and the value of the length-scale parameter relative to the thickness of the plate. The comparison shows that the phase-field models provide very good agreement with the measured stresses and resistance of laminated glass, despite the fact that only one/two cracks are localised using the quasi-static analysis, whereas multiple cracks evolve during the experiment. It was also observed that the stiffness and resistance of the partially fractured laminated glass can be well approximated using a 2D plane-stress model with initially predefined cracks, which provides a better estimation than the one-glass-layer limit. Full article
(This article belongs to the Special Issue Modeling and Testing of Laminated Glass)
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14 pages, 1418 KB  
Article
The Influence of Maltodextrin on the Thermal Transitions and State Diagrams of Fruit Juice Model Systems
by Pedro García-Coronado, Alma Flores-Ramírez, Alicia Grajales-Lagunes, Cesar Godínez-Hernández, Miguel Abud-Archila, Raúl González-García and Miguel A. Ruiz-Cabrera
Polymers 2020, 12(9), 2077; https://doi.org/10.3390/polym12092077 - 12 Sep 2020
Cited by 6 | Viewed by 4872
Abstract
The state diagram, which is defined as a stability map of different states and phases of a food as a function of the solid content and temperature, is regarded as fundamental approach in the design and optimization of processes or storage procedures of [...] Read more.
The state diagram, which is defined as a stability map of different states and phases of a food as a function of the solid content and temperature, is regarded as fundamental approach in the design and optimization of processes or storage procedures of food in the low-, intermediate-, and high-moisture domains. Therefore, in this study, the effects of maltodextrin addition on the freezing points (Tm, Tm) and glass transition temperatures (Tg, Tg) required for the construction of state diagrams of fruit juice model systems by using differential scanning calorimetry methods was investigated. A D-optimal experimental design was used to prepare a total of 25 anhydrous model food systems at various dry mass fractions of fructose, glucose, sucrose, pectin, citric acid, and maltodextrin, in which this last component varied between 0 and 0.8. It was found that maltodextrin mass fractions higher than 0.4 are required to induce significant increases of Tg, Tm, Tg, and Tm curves. From this perspective, maltodextrin is a good alternative as a cryoprotectant and as a carrier agent in the food industry. Furthermore, solute-composition-based mathematical models were developed to evaluate the influence of the chemical composition on the thermal transitions and to predict the state diagrams of fruit juices at different maltodextrin mass fractions. Full article
(This article belongs to the Special Issue Glycopolymers and Polysaccharide-Based Copolymers)
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12 pages, 1339 KB  
Article
Entropies in Alloy Design for High-Entropy and Bulk Glassy Alloys
by Akira Takeuchi, Kenji Amiya, Takeshi Wada, Kunio Yubuta, Wei Zhang and Akihiro Makino
Entropy 2013, 15(9), 3810-3821; https://doi.org/10.3390/e15093810 - 12 Sep 2013
Cited by 115 | Viewed by 12219
Abstract
High-entropy (H-E) alloys, bulk metallic glasses (BMGs) and high-entropy BMGs (HE-BMGs) were statistically analyzed with the help of a database of ternary amorphous alloys. Thermodynamic quantities corresponding to heat of mixing and atomic size differences were calculated as a function of composition of [...] Read more.
High-entropy (H-E) alloys, bulk metallic glasses (BMGs) and high-entropy BMGs (HE-BMGs) were statistically analyzed with the help of a database of ternary amorphous alloys. Thermodynamic quantities corresponding to heat of mixing and atomic size differences were calculated as a function of composition of the multicomponent alloys. Actual calculations were performed for configurational entropy (Sconfig.) in defining the H-E alloys and mismatch entropy (Ss) normalized with Boltzmann constant (kB), together with mixing enthalpy (DHmix) based on Miedema’s empirical model and Delta parameter (d) as a corresponding parameter to Ss/kB. The comparison between DHmixd and DHmix– diagrams for the ternary amorphous alloys revealed Ss/kB ~ (d /22)2. The zones S, S′ and B’s where H-E alloys with disordered solid solutions, ordered alloys and BMGs are plotted in the DHmixd diagram are correlated with the areas in the DHmixSs /kB diagram. The results provide mutual understandings among H-E alloys, BMGs and HE-BMGs. Full article
(This article belongs to the Special Issue High Entropy Alloys)
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21 pages, 922 KB  
Review
Thermodynamic Properties of κ-(BEDT-TTF)2X Salts: Electron Correlations and Superconductivity
by Yasuhiro Nakazawa and Satoshi Yamashita
Crystals 2012, 2(3), 741-761; https://doi.org/10.3390/cryst2030741 - 29 Jun 2012
Cited by 23 | Viewed by 8416
Abstract
Heat capacity measurements of κ-(BEDT-TTF)2X (BEDT-TTF: Bis(ethylendithio) tetrathiafulvalene, X: counteranions) which are classified as two-dimensional (2D) dimer-Mott system are reported. At first, we explain structural and electronic features originated from rigid dimerization in donor arrangement in 2D layers. The antiferromagnetic [...] Read more.
Heat capacity measurements of κ-(BEDT-TTF)2X (BEDT-TTF: Bis(ethylendithio) tetrathiafulvalene, X: counteranions) which are classified as two-dimensional (2D) dimer-Mott system are reported. At first, we explain structural and electronic features originated from rigid dimerization in donor arrangement in 2D layers. The antiferromagnetic Mott insulating phase located at low-pressure region in the phase diagram shows vanishing γ electronic heat capacity coefficient in the heat capacity, which claims opening of a charge-gap in this insulating state. Then, a systematic change of the γ around the Mott boundary region is reported in relation to the glass freezing of ethylene dynamics. The thermodynamic parameters determined by ∆Cp/γTc of 10 K class superconductors, κ-(BEDT-TTF)2Cu(NCS)2 and κ-(BEDT-TTF)2Cu[N(CN)2]Br demonstrate that a rather large gap with a strong coupling character appears around the Fermi-surface. On the other hand, the low temperature heat capacity clearly shows a picture of nodal-gap structure due to an anisotropic pairing. The comparison with lower Tc compounds in the κ-type structure is also performed so as to discuss overall features of the κ-type superconductors. The heat capacity measurements of hole-doped systems containing mercury in the counteranions show an anomalous enhancement of γ, which is consistent with the T1−1 of NMR experiments etc. The results of heat capacity measurements under high pressures are also reported. Full article
(This article belongs to the Special Issue Molecular Conductors)
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