Novel Polar Intermetallic π-Systems along the Zintl Border

1998 ◽  
Vol 547 ◽  
Author(s):  
Arnold M. Guloy ◽  
Zhihong Xu
Keyword(s):  
Electronic Materials ◽  
Structure Property ◽  
Zintl Phases ◽  
Group 13 ◽  
Structure Property Relationships ◽  
Inorganic Systems ◽  
Rich Diversity ◽  
Structures And Properties ◽  
Potential Applications

AbstractStudies have shown that complex Zintl phases exhibit a rich diversity of crystal structures. These have also revealed a remarkable success of the Zintl concept in rationalizing stoichiometry, crystal structure and chemical bonding of many main group intermetallics. Still there are unresolved questions about the usefulness of the concept in explaining structure-property relationships in intermetallics near the Zintl border, and as a rational tool in designing new materials. Limitations of the concept are represented by violations often associated with “electron-deficient” phases that contain Group 13 metalloids. Recent investigations on “electron-deficient” Zintl phases containing post transition metals have led to the synthesis of a number of novel inorganic-intermetallic π-systems. Since unique structures and properties are already apparent in normal Zintl phases, it is anticipated that the exploratory synthesis and characterization of conjugated and multiple-bonded inorganic systems will produce not only unusual crystal chemistry but interesting physical properties as well. We report on new complex Zintl phases that include the semiconducting SrCa2In2Ge - which features [In2Ge]6- chains and represents a novel inorganic conjugated π-system analogous to a polyallyl chain with In-In double bonds, and Ca5In9Sn6 - which contains In trimers, [In3]5- analogous and isoelectronic with the aromatic cyclopropenium cation, [C3H3]+. These unusual materials, Zintl π-systems, represent a promising class of electronic materials with a range of potential applications.

Characterization of Aerogels – Challenges and Prospects

2014 ◽  
Vol 91 ◽  
pp. 54-63 ◽  
Author(s):  
Gudrun Reichenauer
Keyword(s):  
Catalyst Support ◽  
Optical Devices ◽  
Structure Property ◽  
Severe Problem ◽  
The Past ◽  
Structure Property Relationships ◽  
Potential Applications ◽  
Directed Development ◽  
Non Destructive

Aerogels are porous materials with potential applications in fields ranging from thermal insulation, catalyst support, filters, electrical storage, components in optical devices, mechanical damping all the way to drug release. However, careful reliable characterization is the base for both, understanding of fundamental structure - property relationships as well as a directed development of materials and composites for specific applications. The review therefore addressed severe problem upon aerogel characterization that have been identified in the past and presents reliable non-destructive alternatives and novel methods that can be applied for the characterization of aerogels as well as their gel precursors.

scholarly journals Correction: Synthesis and characterization of novel Li-stuffed garnet-like Li5+2xLa3Ta2−xGdxO12 (0 ≤ x ≤ 0.55): structure–property relationships

2017 ◽  
Vol 46 (25) ◽  
pp. 8304-8305
Author(s):  
Dalia M. Abdel Basset ◽  
Suresh Mulmi ◽  
Mohammed S. El-Bana ◽  
Suzan S. Fouad ◽  
Venkataraman Thangadurai
Keyword(s):  
Synthesis And Characterization ◽  
Structure Property ◽  
Dalton Trans ◽  
Structure Property Relationships

Correction for ‘Synthesis and characterization of novel Li-stuffed garnet-like Li5+2xLa3Ta2−xGdxO12 (0 ≤ x ≤ 0.55): structure–property relationships’ by Dalia M. Abdel Basset, et al., Dalton Trans., 2017, 46, 933–946.

scholarly journals Fullerene Dissymmetrization as a Means to Achieve Single Enantiomer Electron Acceptors with Maximized Chiroptical Responsiveness

2020 ◽  
Author(s):  
Wenda Shi ◽  
Francesco Salerno ◽  
Alejandro Santana-Bonilla ◽  
Matthew Ward ◽  
Xueyan Hou ◽  
...  
Keyword(s):  
Electronic Materials ◽  
Light Response ◽  
Electron Acceptors ◽  
Fullerene Cage ◽  
Structure Property ◽  
Organic Electronic Devices ◽  
Organic Electronic ◽  
Structure Property Relationships ◽  
Organic Electronic Materials ◽  
Fast Light

<p>Solubilized fullerene derivatives have revolutionised the development of organic photovoltaic devices, acting as excellent electron acceptors. The addition of solubilizing addends to the fullerene cage results in a large number of isomers, which are generally employed as isomeric mixtures. Moreover, a significant number of these isomers are chiral, which further adds to the isomeric complexity. The opportunities presented by single isomer, and particularly single enantiomer, fullerenes in organic electronic materials and devices are poorly understood. Here we separate 10 pairs of enantiomers from the 19 structural isomers of bis[60]PCBM, using them to elucidate important chiroptical structure-property relationships and demonstrating their application to a single enantiomer circularly polarized (CP) light detecting device. We find that larger chiroptical responses occur through inherent chirality of the fullerene cage and particularly through transitions with low CT character. When used in a single enantiomer organic field-effect transistor device, we demonstrate the potential to discriminate CP light with a fast light response time and with a very high photocurrent dissymmetry factor (<i>g<sub>ph</sub></i> = ±1.35). Our study thus provides key strategies to design fullerenes with large chiroptical responses for use as single enantiomer components of organic electronic devices. We anticipate that our data will position chiral fullerenes as an exciting material class for the growing field of chiral electronic technologies.</p>

scholarly journals Electron Density and Its Relation with Electronic and Optical Properties in 2D Mo/W Dichalcogenides

Nanomaterials ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2221
Author(s):  
Pingping Jiang ◽  
Marie-Christine Record ◽  
Pascal Boulet
Keyword(s):  
Optical Properties ◽  
Lattice Mismatch ◽  
Compressive Strain ◽  
Interatomic Interaction ◽  
Structure Property ◽  
Electronic And Optical Properties ◽  
Cubic Equation ◽  
Structure Property Relationships ◽  
Stacking Order ◽  
Structures And Properties

Two-dimensional MX2 (M = Mo, W; X = S, Se, Te) homo- and heterostructures have attracted extensive attention in electronics and optoelectronics due to their unique structures and properties. In this work, the layer-dependent electronic and optical properties have been studied by varying layer thickness and stacking order. Based on the quantum theory of atoms in molecules, topological analyses on interatomic interactions of layered MX2 and WX2/MoX2, including bond degree (BD), bond length (BL), and bond angle (BA), have been detailed to probe structure-property relationships. Results show that M-X and X-X bonds are strengthened and weakened in layered MX2 compared to the counterparts in bulks. X-X and M-Se/Te are weakened at compressive strain while strengthened at tensile strain and are more responsive to the former than the latter. Discordant BD variation of individual parts of WX2/MoX2 accounts for exclusively distributed electrons and holes, yielding type-II band offsets. X-X BL correlates positively to binding energy (Eb), while X-X BA correlates negatively to lattice mismatch (lm). The resulting interlayer distance limitation evidences constraint-free lattice of vdW structure. Finally, the connection between microscopic interatomic interaction and macroscopic electromagnetic behavior has been quantified firstly by a cubic equation relating to weighted BD summation and static dielectric constant.

scholarly journals Barbituric Acid Based Fluorogens: Synthesis, Aggregation-Induced Emission, and Protein Fibril Detection

Molecules ◽  
2019 ◽  
Vol 25 (1) ◽  
pp. 32 ◽  
Author(s):  
Siyang Ding ◽  
Bicheng Yao ◽  
Louis Schobben ◽  
Yuning Hong
Keyword(s):  
Barbituric Acid ◽  
Fluorescent Dyes ◽  
Photophysical Properties ◽  
Wavelength Region ◽  
Structure Property ◽  
Aggregation Induced Emission ◽  
Long Wavelength ◽  
Structure Property Relationships ◽  
Potential Applications ◽  
Protein Fibril

Fluorescent dyes, especially those emitting in the long wavelength region, are excellent candidates in the area of bioassay and bioimaging. In this work, we report a series of simple organic fluorescent dyes consisting of electron-donating aniline groups and electron-withdrawing barbituric acid groups. These dyes are very easy to construct while emitting strongly in the red region in their solid state. The photophysical properties of these dyes, such as solvatochromism and aggregation-induced emission, are systematically characterized. Afterward, the structure–property relationships of these barbituric acid based fluorogens are discussed. Finally, we demonstrate their potential applications for protein amyloid fibril detection.

Preparation and Characterization of Several Conducting Transition Metal Oxides

1989 ◽  
Vol 156 ◽  
Author(s):  
Aaron Wold ◽  
Kirby Dwight
Keyword(s):  
Transition Metal ◽  
Single Crystal ◽  
Metal Oxides ◽  
Transition Metal Oxides ◽  
Structure Property ◽  
Metallic Behavior ◽  
Structure Property Relationships ◽  
Conduction Bands ◽  
Metal Metal

ABSTRACTThe structure-property relationships of several conducting transition metal oxides, as well as their preparative methods, are presented in this paper. The importance of preparing homogeneous phases with precisely known stoichiometry is emphasized. A comparison is also made of the various techniques used to prepare both polycrystalline and single crystal samples. For transition metal oxides, the metallic properties are discussed either in terms of metal-metal distances which are short enough to result in metallic behavior, or in terms of the formation of a П* conduction band resulting from covalent metal-oxygen interactions. Metallic behavior is observed when the conduction bands are populated with either electrons or holes. The concentration of these carriers can be affected by either cation or anion substitutions. The discussion in this presentation will be limited to the elements Re, Ti, V, Cr, Mo, and Cu.

Imidazole-Based Solvents and Membranes for CO2 Capture Applications

2014 ◽  
Vol 1673 ◽  
Author(s):  
Jason E. Bara ◽  
Matthew S. Shannon ◽  
W. Jeffrey Horne ◽  
John W. Whitley ◽  
Haining Liu ◽  
...  
Keyword(s):  
Flue Gas ◽  
Process Design ◽  
Predictive Models ◽  
Power Plants ◽  
Absorption Capacity ◽  
Computational Studies ◽  
Structure Property ◽  
Structure Property Relationships ◽  
Imidazole Compounds

ABSTRACTImidazoles present a tunable, versatile and economical platform for the development of novel liquid solvents and polymer membranes for CO2 capture. An overview of our studies in this area is presented, with emphasis on characterization of structure-property relationships in imidazole-based materials through both experimental and computational studies. To this end, a growing library of systematically varied imidazole compounds has been synthesized using only commercial available starting materials and straightforward reactions. Using this library of compounds, we have sought to understand and develop predictive models for thermophysical properties relating to process design, including: density, viscosity, vapor pressure, pKa and CO2 absorption capacity. Furthermore, we have discovered that imidazoles are stable in the presence of SO2 and can form reversible 1:1 adducts, which can be beneficial as SO2 is typically present at ppm levels alongside CO2 in flue gas from coal-fired power plants.

Mechanical and Viscoelastic Characterization of Hyperbranched Polyisobutylenes

2002 ◽  
Vol 75 (5) ◽  
pp. 853-864 ◽  
Author(s):  
Judit E. Puskas ◽  
Christophe Paulo ◽  
Volker Altstädt
Keyword(s):  
Molecular Weight ◽  
Butyl Rubber ◽  
Structure Property ◽  
Carbocationic Polymerization ◽  
Molecular Weights ◽  
Structure Property Relationships ◽  
Molecular Weight Distributions ◽  
Weight Distributions ◽  
Living Carbocationic Polymerization

Abstract Structure-property relationships were investigated in hyperbranched polyisobutylenes, in comparison with commercial linear butyl rubber. The gel-free, soluble hyperbranched polyisobutylenes, synthesized by living carbocationic polymerization, had molecular weights, Mw≈400,000 to 1,000,000 g/mol, molecular weight distributions, MWD ≈1.2 to 2.6, and branching frequencies, BR ≈ 4 to 60. The mechanical and viscoelastic characterization of these polymers revealed interesting properties, including the characteristics of crosslinked rubbers.

In situ characterization of Cu–Co oxides for catalytic application

2015 ◽  
Vol 177 ◽  
pp. 249-262 ◽  
Author(s):  
Z. Y. Tian ◽  
H. Vieker ◽  
P. Mountapmbeme Kouotou ◽  
A. Beyer
Keyword(s):  
Thermal Properties ◽  
Chemical Vapor ◽  
Functional Materials ◽  
Catalytic Performance ◽  
Structure Property ◽  
Temperature Oxidation ◽  
Spatially Resolved ◽  
Structure Property Relationships ◽  
Potential Applications

In situ emission and absorption FTIR methods were employed to characterize the spatially resolved structure of binary Co–Cu oxides for low-temperature oxidation of CO and propene. Co–Cu oxide catalysts were controllably synthesized by pulsed-spray evaporation chemical vapor deposition. XRD, FTIR, XPS, UV-vis and helium ion microscopy (HIM) were employed to characterize the as-prepared thin films in terms of structure, composition, optical and thermal properties as well as morphology. In situ emission FTIR spectroscopy indicates that Co3O4, CuCo2O4 and CuO are thermally stable at 650, 655 and 450 °C, respectively. The catalytic tests with absorption FTIR display that the involvement of Co–Cu oxides can initiate CO and C3H6 oxidation at lower temperatures. The results indicate that in situ emission and absorption FTIR are useful techniques to explore the thermal properties and catalytic performance of functional materials, allowing many potential applications in tailoring their temporally and spatially resolved structure-property relationships.

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