scholarly journals Contributions of mechanical bonding and chemical bonding to high-temperature hermeticity of glass-to-metal compression seals

2021 ◽  
Vol 202 ◽  
pp. 109579
Author(s):  
Kangjia Hu ◽  
Shenhou Li ◽  
Zhichun Fan ◽  
He Yan ◽  
Xuewei Liang ◽  
...  
Keyword(s):  
High Temperature ◽  
Chemical Bonding ◽  
Mechanical Bonding

Bonding Constraints at Interfaces Between Crystalline Si and Stacked Gate Dielectrics

1999 ◽  
Vol 567 ◽  
Author(s):  
G. Lucovsky ◽  
J.C. Phillips
Keyword(s):  
Metal Oxides ◽  
Transition Metal Oxides ◽  
Chemical Bonding ◽  
Gate Dielectrics ◽  
Nuclear Charge ◽  
Dielectric Materials ◽  
Band Offset ◽  
High K ◽  
Dielectric Interfaces ◽  
Mechanical Bonding

ABSTRACTThis paper discusses chemical bonding effects at Si-dielectric interfaces that are important in the implementation of alternative gate dielectrics including: i) the character of interfacial bonds, either isovalent with bond and nuclear charge balanced as in Si-SiO2, or heterovalent, with an inherent mismatch between bond and nuclear charge, ii) mechanical bonding constraints related to the average number of bonds/atom, Nay, and iii) band offset energies that are reduced in transition metal oxides due to the d-state origins of the conduction band states. Applications are made to specific classes of dielectric materials including i) nitrides and oxide/nitride stacks and ii) alternative high-K gate materials.

Magnesium intermetallics: synthesis and structure of Eu2Pt2Mg and Sr2Pt2Mg

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Maximilian Kai Reimann ◽  
Rainer Pöttgen
Keyword(s):  
High Temperature ◽  
Chemical Bonding ◽  
Valence Electron ◽  
Intermetallic Phases ◽  
Type Structure

Abstract The intermetallic phases Sr2Pt2Mg and Eu2Pt2Mg were obtained by reaction of the elements in sealed tantalum tubes at high temperature. Sr2Pt2Mg crystallizes with the monoclinic Ca2Ir2Si type (C2/c, a = 1020.7(7), b = 597.7(4), c = 827.0(4) pm, β = 103.37(5)°), while Eu2Pt2Mg adopts the orthorhombic W2CoB2-type structure (Immm, a = 440.31(5), b = 582.20(6), c = 914.11(9) pm, wR = 0.0359, 277 F 2 values, 14 variables). The magnesium atoms in both structures are coordinated by four Pt2 dumb-bells with a rectangular planar coordination in Eu2Pt2Mg (268 pm Pt–Mg) and a distorted tetrahedral one in Sr2Pt2Mg (273–275 pm Pt–Mg). The Pt–Pt distances are 277 pm in the europium and 269 pm in the strontium compound. The polyanionic [Pt2Mg] units are planar in Eu2Pt2Mg and separated by the europium atoms. The Sr2Pt2Mg structure shows the motif of hexagonal rod packing for the [Pt2Mg] rows that are embedded in a strontium matrix. Chemical bonding and the influence of the valence electron count on the formation of the structure types are discussed.

Crystal Structure and Chemical Bonding of the High-Temperature Phase of AgN3.

ChemInform ◽  
2007 ◽  
Vol 38 (17) ◽  
Author(s):  
Carsten L. Schmidt ◽  
Robert Dinnebier ◽  
Ulrich Wedig ◽  
Martin Jansen
Keyword(s):  
Crystal Structure ◽  
High Temperature ◽  
Chemical Bonding ◽  
High Temperature Phase ◽  
Temperature Phase

Chemical bonding in high-temperature YBa2Cu3O7 superconductors

1990 ◽  
Vol 30 (5) ◽  
pp. 709-712
Author(s):  
D. L. Novikov ◽  
M. V. Ryzhkov ◽  
V. A. Gubanov
Keyword(s):  
High Temperature ◽  
Chemical Bonding

scholarly journals Chemical bonding and crystal structure of Zr-based intermetallic high-temperature shape memory alloys

2013 ◽  
Vol 6 (3/4) ◽  
pp. 205-208 ◽  
Author(s):  
Georgiy FIRSTOV ◽  
◽  
Yuri KOVAL ◽  
Andrei TIMOSHEVSKII ◽  
Sergey YABLONOVSKII ◽  
...  
Keyword(s):  
Crystal Structure ◽  
High Temperature ◽  
Shape Memory Alloys ◽  
Shape Memory ◽  
Chemical Bonding

Compton Spectroscopy and Chemical Bonding

2001 ◽  
Vol 215 (10) ◽  
Author(s):  
A. Shukla ◽  
B. Barbiellini ◽  
T. Buslaps ◽  
P. Suortti
Keyword(s):  
High Temperature ◽  
Synchrotron Radiation ◽  
Chemical Bonding ◽  
Molecular Crystal ◽  
High Temperature Superconductor ◽  
Condensed Matter ◽  
Condensed Matter Physics ◽  
Compton Profile ◽  
Computational Tools ◽  
Practical Applications

In this article we show with the help of two examples how Compton spectroscopy may be used to study the effect of chemical bonding in materials as diverse as a molecular crystal and a high temperature superconductor. Compton spectroscopy has a long history as an investigative method in condensed matter physics and in fact the realisation that the Compton profile is sensitive to the effects of chemical bonding dates back at least fifty years. In the seventies, through the efforts of Weyrich [1] and others [2,3], practical applications of this realisation were first achieved. We argue that such studies are more and more relevant thanks to the availability of synchrotron radiation and efficient computational tools.

scholarly journals High-Temperature Crystal Structure and Chemical Bonding in Thermoelectric Germanium Selenide (GeSe)

2017 ◽  
Vol 23 (28) ◽  
pp. 6888-6895 ◽  
Author(s):  
Mattia Sist ◽  
Carlo Gatti ◽  
Peter Nørby ◽  
Simone Cenedese ◽  
Hidetaka Kasai ◽  
...  
Keyword(s):  
Crystal Structure ◽  
High Temperature ◽  
Chemical Bonding ◽  
Germanium Selenide

Chemical Interactions at Metal-Polymer Interfaces

1984 ◽  
Vol 40 ◽  
Author(s):  
P. O. Hahn ◽  
G. W. Rubloff ◽  
J. W. Bartha ◽  
F. Legoues ◽  
R. Tromp ◽  
...  
Keyword(s):  
Electronic Structure ◽  
High Temperature ◽  
Molecular Orbital ◽  
Chemical Bonding ◽  
Chemical Properties ◽  
Molecular Orbital Calculations ◽  
Polymer Interfaces ◽  
Interface Morphology ◽  
Bulk Chemical ◽  
Metal Polymer

AbstractThis paper summarizes recent studies on metal-polymer interfaces for Cu, Ni and Cr on a high temperature polymer, polyimide. First some surface and bulk chemical properties of polyimide are described briefly, as measured with surface spectroscopies and verified by theoretical molecular orbital calculations. Then the chemical bonding and reactivity of the three interfaces are described and discussed in light of experimental observations of electronic structure, composition and interface morphology. The chemical trend of increasing reactivity of the interface is illustrated by comparing results from Cu to Cr.

Materials with ZrCuSiAs-type Structure

2008 ◽  
Vol 63 (10) ◽  
pp. 1135-1148 ◽  
Author(s):  
Rainer Pöttgen ◽  
Dirk Johrendt
Keyword(s):  
Optical Properties ◽  
Rare Earth ◽  
High Temperature ◽  
Chemical Bonding ◽  
Earth Element ◽  
High Temperature Superconductivity ◽  
Magnetic Ordering ◽  
Type Structure ◽  
Crystal Chemical ◽  
Semiconducting Behavior

AbstractThe discovery of high-temperature superconductivity in the fluoride-doped arsenide oxides REFeAs(O1−xFx) (RE = early rare earth element) with transition temperatures as high as 55 K has led to a true renaissance in superconductivity research. These arsenide oxides constitute a rather small fraction of a much larger family of compounds with the tetragonal ZrCuSiAs-type structure (space group P4/nmm), among them pnictide oxides and fluorides, chalcogenide oxides and fluorides as well as silicide and germanide hydrides. Besides the spectacular superconductivity, these materials have further interesting properties with respect to magnetic ordering, transparent semiconducting behavior or optical properties. The crystal chemical and chemical bonding peculiarities as well as the broadly varying physical properties are reviewed herein.

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