Blue Phosphorescent trans-N-Heterocyclic Carbene Platinum Acetylides: Dependence on Energy Gap and Conformation

A high glass transition, triplet energy gap and electron mobility material, TPOTP, is readily synthesized. It can serve as an efficient universal electron transporter and exciton blocker for blue, green and red phosphorescent OLEDs.

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Wide-Energy-Gap Host Materials for Blue Phosphorescent Organic Light-Emitting Diodes

Chemistry of Materials ◽

10.1021/cm8032302 ◽

2009 ◽

Vol 21 (7) ◽

pp. 1333-1342 ◽

Cited By ~ 69

Author(s):

Shanghui Ye ◽

Yunqi Liu ◽

Chong-an Di ◽

Hongxia Xi ◽

Weiping Wu ◽

...

Keyword(s):

Light Emitting Diodes ◽

Energy Gap ◽

Organic Light Emitting Diodes ◽

Light Emitting ◽

Organic Light ◽

Host Materials ◽

Wide Energy ◽

Blue Phosphorescent

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Silafluorene moieties as promising building blocks for constructing wide-energy-gap host materials of blue phosphorescent organic light-emitting devices

Science China Chemistry ◽

10.1007/s11426-015-5329-6 ◽

2015 ◽

Vol 58 (6) ◽

pp. 993-998 ◽

Cited By ~ 4

Author(s):

Dongdong Wang ◽

Qingqing Liu ◽

Yue Yu ◽

Yong Wu ◽

Xinwen Zhang ◽

...

Keyword(s):

Energy Gap ◽

Building Blocks ◽

Light Emitting ◽

Light Emitting Devices ◽

Organic Light ◽

Host Materials ◽

Wide Energy ◽

Organic Light Emitting Devices ◽

Blue Phosphorescent

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New design strategy for chemically-stable blue phosphorescent materials: improving the energy gap between the T1 and 3MC states

Physical Chemistry Chemical Physics ◽

10.1039/c9cp05781a ◽

2021 ◽

Vol 23 (5) ◽

pp. 3543-3551

Author(s):

Sunwoo Kang ◽

Taekyung Kim ◽

Jin Yong Lee

Keyword(s):

Density Functional Theory ◽

Excited State ◽

Dft Calculations ◽

Chemical Stability ◽

Density Functional ◽

Energy Gap ◽

Design Strategy ◽

Functional Theory ◽

Blue Phosphorescent

A series of Ir- and Pt-based blue phosphorescent materials were theoretically investigated by means of density functional theory (DFT) calculations to improve their chemical stability in the excited state.

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Formation of high temperature phase in flash-evaporated SnSe films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100176629 ◽

1990 ◽

Vol 48 (4) ◽

pp. 698-699

Author(s):

J.P.S. Hanjra

Keyword(s):

Thin Films ◽

Electrical Properties ◽

Energy Gap ◽

Dominant Role ◽

Fine Powder ◽

High Temperature Phase ◽

Temperature Phase ◽

Water Mixture ◽

Flash Evaporation ◽

Photovoltaic Applications

Tin mono selenide (SnSe) with an energy gap of about 1 eV is a potential material for photovoltaic applications. Various authors have studied the structure, electronic and photoelectronic properties of thin films of SnSe grown by various deposition techniques. However, for practical photovoltaic junctions the electrical properties of SnSe films need improvement. We have carried out investigations into the properties of flash evaporated SnSe films. In this paper we report our results on the structure, which plays a dominant role on the electrical properties of thin films by TEM, SEM, and electron diffraction (ED).Thin films of SnSe were deposited by flash evaporation of SnSe fine powder prepared from high purity Sn and Se, onto glass, mica and KCl substrates in a vacuum of 2Ø micro Torr. A 15% HF + 2Ø% HNO3 solution was used to detach SnSe film from the glass and mica substrates whereas the film deposited on KCl substrate was floated over an ethanol water mixture by dissolution of KCl. The floating films were picked up on the grids for their EM analysis.

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Effect of the structural changes on the mechanical properties of the sintered films

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v12i1.168 ◽

2016 ◽

Vol 12 (1) ◽

pp. 4141-4144

Author(s):

Garima Jain

Keyword(s):

Crystallite Size ◽

Lattice Constant ◽

Structural Changes ◽

Structural Investigation ◽

Energy Gap ◽

Lattice Parameter ◽

Metal Chalcogenides ◽

Optical Energy Gap ◽

Tin Telluride ◽

Physical Quantities

Polycrystalline films of tin telluride were prepared by sintering technique. The structural investigation of the films with different thicknesses enables to determine lattice parameter, crystallite size and strain existing in the films. The XRD traces showed that strain was tensile in nature. The crystallite size increases with thickness while strain decreases. Higher the value of tensile strain, larger is the lattice constant. The optical energy gap shows a descending nature with increasing strain and so with the lattice constant. Such an attempt made to delve into interdependence of basic physical quantities helps to explore the properties of SnTe and utilize it as an alternative to heavy metal chalcogenides in various technological applications. Â

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Structure, Stability and Water Adsorption on Ultra-Thin TiO2 Supported on TiN

10.26434/chemrxiv.8425367.v1 ◽

2019 ◽

Author(s):

Jose Julio Gutierrez Moreno ◽

Marco Fronzi ◽

Pierre Lovera ◽

alan O'Riordan ◽

Mike J Ford ◽

...

Keyword(s):

Density Functional ◽

Water Adsorption ◽

Chemical Potential ◽

Energy Gap ◽

Molecular Water ◽

Structure Stability ◽

Ambient Conditions ◽

Rutile Structure ◽

The Stability ◽

The One

Interfacial metal-oxide systems with ultrathin oxide layers are of high interest for their use in catalysis. In this study, we present a density functional theory (DFT) investigation of the structure of ultrathin rutile layers (one and two TiO2 layers) supported on TiN and the stability of water on these interfacial structures. The rutile layers are stabilized on the TiN surface through the formation of interfacial Ti–O bonds. Charge transfer from the TiN substrate leads to the formation of reduced Ti3+ cations in TiO2. The structure of the one-layer oxide slab is strongly distorted at the interface, while the thicker TiO2 layer preserves the rutile structure. The energy cost for the formation of a single O vacancy in the one-layer oxide slab is only 0.5 eV with respect to the ideal interface. For the two-layer oxide slab, the introduction of several vacancies in an already non-stoichiometric system becomes progressively more favourable, which indicates the stability of the highly non-stoichiometric interfaces. Isolated water molecules dissociate when adsorbed at the TiO2 layers. At higher coverages the preference is for molecular water adsorption. Our ab initio thermodynamics calculations show the fully water covered stoichiometric models as the most stable structure at typical ambient conditions. Interfacial models with multiple vacancies are most stable at low (reducing) oxygen chemical potential values. A water monolayer adsorbs dissociatively on the highly distorted 2-layer TiO1.75-TiN interface, where the Ti3+ states lying above the top of the valence band contribute to a significant reduction of the energy gap compared to the stoichiometric TiO2-TiN model. Our results provide a guide for the design of novel interfacial systems containing ultrathin TiO2 with potential application as photocatalytic water splitting devices.

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Molecular Investigations of the Newly Synthesized Azomethines as Antioxidants: Theoretical and Experimental Studies

Current Molecular Medicine ◽

10.2174/1566524019666190509102620 ◽

2019 ◽

Vol 19 (6) ◽

pp. 419-433 ◽

Cited By ~ 1

Author(s):

Siyamak Shahab ◽

Masoome Sheikhi ◽

Liudmila Filippovich ◽

Evgenij Dikusar ◽

Anhelina Pazniak ◽

...

Keyword(s):

Density Functional ◽

Energy Gap ◽

Experimental Studies ◽

Antioxidant Property ◽

Nbo Analysis ◽

Antioxidant Potential ◽

Functional Theory ◽

Homo And Lumo ◽

Intramolecular Hydrogen ◽

Activity Mechanism

: In this study, the antioxidant property of new synthesized azomethins has been investigated as theoretical and experimental. Methods and Results: Density functional theory (DFT) was employed to investigate the Bond Dissociation Enthalpy (BDE), Mulliken Charges, NBO analysis, Ionization Potential (IP), Electron Affinities (EA), HOMO and LUMO energies, Hardness (η), Softness (S), Electronegativity (µ), Electrophilic Index (ω), Electron Donating Power (ω-), Electron Accepting Power (ω+) and Energy Gap (Eg) in order to deduce scavenging action of the two new synthesized azomethines (FD-1 and FD-2). Spin density calculations and NBO analysis were also carried out to understand the antioxidant activity mechanism. Comparison of BDE of FD-1 and FD-2 indicate the weal antioxidant potential of these structures. Conclusion: FD-1 and FD-2 have very high antioxidant potential due to the planarity and formation of intramolecular hydrogen bonds.

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