Atomic and Molecular Electron Affinities: Photoelectron Experiments and Theoretical Computations
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Densifying Metal Hydrides with High Temperature and Pressure
3,784,682 United States Patent Office Patented Jan. 8, 1974 feet the true density. That is, by this method only theo- 3,784,682 retical or near theoretical densities can be obtained by DENSIFYING METAL HYDRIDES WITH HIGH making the material quite free from porosity (p. 354). TEMPERATURE AND PRESSURE The true density remains the same. Leonard M. NiebylsM, Birmingham, Mich., assignor to Ethyl Corporation, Richmond, Va. SUMMARY OF THE INVENTION No Drawing. Continuation-in-part of abandoned applica- tion Ser. No. 392,370, Aug. 24, 1964. This application The process of this invention provides a practical Apr. 9,1968, Ser. No. 721,135 method of increasing the true density of hydrides of Int. CI. COlb 6/00, 6/06 metals of Groups II-A, II-B, III-A and III-B of the U.S. CI. 423—645 8 Claims Periodic Table. More specifically, true densities of said 10 metal hydrides may be substantially increased by subject- ing a hydride to superatmospheric pressures at or above ABSTRACT OF THE DISCLOSURE fusion temperatures. When beryllium hydride is subjected A method of increasing the density of a hydride of a to this process, a material having a density of at least metal of Groups II-A, II-B, III-A and III-B of the 0.69 g./cc. is obtained. It may or may not be crystalline. Periodic Table which comprises subjecting a hydride to 15 a pressure of from about 50,000 p.s.i. to about 900,000 DESCRIPTION OF THE PREFERRED p.s.i. at or above the fusion temperature of the hydride; EMBODIMENT i.e., between about 65° C. -
Global Minimum Beryllium Hydride Sheet with Novel Negative Poisson's Ratio: first-Principles Cite This: RSC Adv.,2018,8, 19432 Calculations
RSC Advances View Article Online PAPER View Journal | View Issue Global minimum beryllium hydride sheet with novel negative Poisson's ratio: first-principles Cite this: RSC Adv.,2018,8, 19432 calculations Feng Li, *ab Urs Aeberhard,b Hong Wu,a Man Qiaoc and Yafei Li *c As one of the most prominent metal-hydrides, beryllium hydride has received much attention over the past several decades, since 1978, and is considered as an important hydrogen storage material. By reducing the dimensionality from 3 to 2, the beryllium hydride monolayer is isoelectronic with graphene; thus the existence of its two-dimensional (2D) form is theoretically feasible and experimentally expected. However, little is known about its 2D form. In this work, by a global minimum search with the particle swarm optimization method via density functional theory computations, we predicted two new stable structures for the beryllium hydride sheets, named a–BeH2 and b–BeH2 monolayers. Both structures have more favorable thermodynamic stability than the recently reported planar square form (Nanoscale, Creative Commons Attribution-NonCommercial 3.0 Unported Licence. 2017, 9, 8740), due to the forming of multicenter delocalized Be–H bonds. Utilizing the recently developed SSAdNDP method, we revealed that three-center-two-electron (3c–2e) delocalized Be–H bonds are formed in the a–BeH2 monolayer, while for the b–BeH2 monolayer, novel four-center-two- electron (4c–2e) delocalized bonds are observed in the 2D system for the first time. These unique multicenter chemical bonds endow both a– and b–BeH2 with high structural stabilities, which are further confirmed by the absence of imaginary modes in their phonon spectra, the favorable formation energies comparable to bulk and cluster beryllium hydride, and the high mechanical strength. -
Global Minimum Beryllium Hydride Sheet with Novel Negative Poisson's Ratio: first-Principles Cite This: RSC Adv.,2018,8, 19432 Calculations
RSC Advances View Article Online PAPER View Journal | View Issue Global minimum beryllium hydride sheet with novel negative Poisson's ratio: first-principles Cite this: RSC Adv.,2018,8, 19432 calculations Feng Li, *ab Urs Aeberhard,b Hong Wu,a Man Qiaoc and Yafei Li *c As one of the most prominent metal-hydrides, beryllium hydride has received much attention over the past several decades, since 1978, and is considered as an important hydrogen storage material. By reducing the dimensionality from 3 to 2, the beryllium hydride monolayer is isoelectronic with graphene; thus the existence of its two-dimensional (2D) form is theoretically feasible and experimentally expected. However, little is known about its 2D form. In this work, by a global minimum search with the particle swarm optimization method via density functional theory computations, we predicted two new stable structures for the beryllium hydride sheets, named a–BeH2 and b–BeH2 monolayers. Both structures have more favorable thermodynamic stability than the recently reported planar square form (Nanoscale, Creative Commons Attribution-NonCommercial 3.0 Unported Licence. 2017, 9, 8740), due to the forming of multicenter delocalized Be–H bonds. Utilizing the recently developed SSAdNDP method, we revealed that three-center-two-electron (3c–2e) delocalized Be–H bonds are formed in the a–BeH2 monolayer, while for the b–BeH2 monolayer, novel four-center-two- electron (4c–2e) delocalized bonds are observed in the 2D system for the first time. These unique multicenter chemical bonds endow both a– and b–BeH2 with high structural stabilities, which are further confirmed by the absence of imaginary modes in their phonon spectra, the favorable formation energies comparable to bulk and cluster beryllium hydride, and the high mechanical strength. -
Operation Permit Application
Un; iy^\ tea 0 9 o Operation Permit Application Located at: 2002 North Orient Road Tampa, Florida 33619 (813) 623-5302 o Training Program TRAINING PROGRAM for Universal Waste & Transit Orient Road Tampa, Florida m ^^^^ HAZARDOUS WAb 1 P.ER^AlTTlNG TRAINING PROGRAM MASTER INDEX CHAPTER 1: Introduction Tab A CHAPTER 2: General Safety Manual Tab B CHAPTER 3: Protective Clothing Guide Tab C CHAPTER 4: Respiratory Training Program Tab D APPENDIX 1: Respiratory Training Program II Tab E CHAPTER 5: Basic Emergency Training Guide Tab F CHAPTER 6: Facility Operations Manual Tab G CHAPTER 7: Land Ban Certificates Tab H CHAPTER 8: Employee Certification Statement Tab. I CHAPTER ONE INTRODUCTION prepared by Universal Waste & Transit Orient Road Tampa Florida Introducti on STORAGE/TREATMENT PERSONNEL TRAINING PROGRAM All personnel involved in any handling, transportation, storage or treatment of hazardous wastes are required to start the enclosed training program within one-week after the initiation of employment at Universal Waste & Transit. This training program includes the following: Safety Equipment Personnel Protective Equipment First Aid & CPR Waste Handling Procedures Release Prevention & Response Decontamination Procedures Facility Operations Facility Maintenance Transportation Requirements Recordkeeping We highly recommend that all personnel involved in the handling, transportation, storage or treatment of hazardous wastes actively pursue additional technical courses at either the University of South Florida, or Tampa Junior College. Recommended courses would include general chemistry; analytical chemistry; environmental chemistry; toxicology; and additional safety and health related topics. Universal Waste & Transit will pay all registration, tuition and book fees for any courses which are job related. The only requirement is the successful completion of that course. -
Shriver & Atkins Problems for Chapter 9
Molecular Modeling Problems Chapter 9 1. Lithium Aluminum Hydride and Sodium Borohydride. Among the most important sources of hydride anion as a reducing agent are lithium aluminum hydride (LiAlH4, commonly referred to as LAH) and sodium borohydride (NaBH4). Are these molecules better represented as weak complexes between LIH and AlH3 and between NaH and BH3, + - + - respectively, or as ion pairs, LI AlH4 and Na BH4 , or are they somewhere in between? To decide, guess a structure for each (don’t impose symmetry) and starting from this structure, obtain an equilibrium geometry and infrared spectrum. Use the B3LYP/6-31G* model. You may wish to start with more than one guess geometry for each, in which case use the one that leads to the lowest total energy. Compare geometries of your structures - - with those of the possible neutral and ionic fragments (LiH, AlH3, AlH4 , BH3 and BH4 ) to you decide the “best” description. 2. Zero-Point Energy and Bond Dissociation Energy. The energy obtained from a quantum chemical calculation refers to a molecule “resting” at the bottom of a potential energy surface. The “measured” energy (enthalpy) refers to a molecule residing in the lowest vibrational level. The difference is referred to as the zero-point energy and is proportional to the sum of all the vibrational frequencies. Zero-point energy largely cancels in many types of chemical reactions, but does not cancel in bond dissociation reactions. Explain why for the specific case of bond dissociation of a diatomic molecule. Use the B3LYP/6-31G* model to calculate XH bond dissociation energies in hydrogen molecule, lithium hydride, methane, ammonia, water and hydrogen fluoride. -
Bonding and Structure of Disilenes and Related Unsaturated Group-14 Element Compounds
No. 5] Proc. Jpn. Acad., Ser. B 88 (2012) 167 Review Bonding and structure of disilenes and related unsaturated group-14 element compounds † By Mitsuo KIRA*1, (Communicated by Hitosi NOZAKI, M.J.A.) Abstract: Structure and properties of silicon-silicon doubly bonded compounds (disilenes) are shown to be remarkably different from those of alkenes. X-Ray structural analysis of a series of acyclic tetrakis(trialkylsilyl)disilenes has shown that the geometry of these disilenes is quite flexible, and planar, twist or trans-bent depending on the bulkiness and shape of the trialkylsilyl substituents. Thermal and photochemical interconversion between a cyclotetrasilene and the corresponding bicyclo[1.1.0]tetrasilane occurs via either 1,2-silyl migration or a concerted electrocyclic reaction depending on the ring substituents without intermediacy of the corresponding tetrasila-1,3-diene. Theoretical and spectroscopic studies of a stable spiropentasiladiene have revealed a unique feature of the spiroconjugation in this system. Starting with a stable dialkylsilylene, a number of elaborated disilenes including trisilaallene and its germanium congeners are synthesized. Unlike carbon allenes, the trisilaallene has remarkably bent and fluxional geometry, suggesting the importance of the :-<* orbital mixing. 14-Electron three-coordinate disilene- palladium complexes are found to have much stronger :-complex character than related 16-electron tetracoordinate complexes. Keywords: silicon, germanium, double bond, synthesis, structure, theoretical calculations -
Thermal Decomposition of Some Group I, II, and III Metal Alkyls
* ~.py219 RME56L18 .-.—. RESEARCH MEMORANDUM THERMAL DECOMPOSITION OF SOME GROUP I, H, AND 111 METAL ALKYLS By Louis Ros enblum Lewis Flight Propulsion Laboratory Cleveland, Ohio Lkssi#i(:.””2!i Ci.l?c.[td((IiCA”.fli-dc’[a,...u.h&l&.ss.\E$.&.&....) ‘3;:.~l%. NRS(-3%ZA PA ihbma-z=..w L-.FFI:LR AI.I:I+GR!?ED10 CI{ANGC) )(2.....Jyka,..lii... ...... By ....... .,. ....... ..-,-. ,..,2 w< ............................. ‘-.”.”G~~DE””aFof;ic~RMAKING.......cI-IMtG~).......................... )+m*61CLwmEDmCmENT .. ... .. .. ... ... .. .. .. .. ‘rbIamateti Contdnslnf014MMH.mcmngthaNauOnalDefenseof tlmUllltadSta!eaW-lthbtb UlnaII@ of tb espionageMm, lltle M, U.& C., &a. ‘7S3 d ‘794, tlM tmumlsaion or remlalim d wMch in my —r to an uautbrwd pmon Is pmbliitad b lnw. NATtONAL ADVISORY COMMITTEE FOR AERONAUTICS WASHINGTON February 15, 1957 TECH LIBRARYKAFB,NM Illllllllllllllllllllllllllllllilllll NACA RM E56L18 OM’=123 NATIONAL ADVISORY COMMJ3?TEEFOR AERONAUTICS RXE!JMRCHMEMORANDUM THERMAL DECOMPOSITIONOF SOMEGROW 1, II, AND III MEI!KLJKJCYCS BY Louis Rosenblum SUMMARY A mechanism is presented for the thermal decomposition of sodium, lithium, beryU.ium, magnesium, aluminum, and boron al&yls and for the reverse reaction, the addition of olefins to metal.hydrides. These re- actions are shown to be nonradical and to probably proceed through a cyclic intermediate. Calculations have been made of the free energies, heats, entropies, and activation energies of reaction for the decomposi- tion of some boron and aluminum alkyls. Decomposition both by the non- radical path and a radical path were considered for purposes of compari- son. The nonradical decomposition at 298° to 400° K (25° to 127° C) is not spontaneous, while a rafical deco~osition is. -
Studies on Group Ii Metal Alkyls Particularly Those of Beryllium
Durham E-Theses Studies on group ii metal alkyls particularly those of beryllium Robert, P.D. How to cite: Robert, P.D. (1968) Studies on group ii metal alkyls particularly those of beryllium, Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/8717/ Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in Durham E-Theses • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full Durham E-Theses policy for further details. Academic Support Oce, Durham University, University Oce, Old Elvet, Durham DH1 3HP e-mail: [email protected] Tel: +44 0191 334 6107 http://etheses.dur.ac.uk STUDIES ON GROUP II METAL ALKYLS PARTICULARLY THOSE OF BERYLLIUM by P.D. ROBERTS, B.Sc. A thesis submitted for the Degree of Doctor of Philosophy in the University of Durham JULY 1968 Acknowledgements The author wishes to thank Professor G.E. Coates, M.A. , D.Sc, F.R.I.C., under whose supervision this research was carried out, for his constant encouragement and valuable advice. Thanks are also given to Dr. A.J. Downs, formerly of the University of Newcastle upon Tyne, for his help with vibrational spectroscopy and to members of this department, especially Dr. -
Beryllium Chloride Apparatus. Figure M
Durham E-Theses Organic and hydride chemistry of beryllium Bell, N.A How to cite: Bell, N.A (1964) Organic and hydride chemistry of beryllium, Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/8894/ Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in Durham E-Theses • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full Durham E-Theses policy for further details. Academic Support Oce, Durham University, University Oce, Old Elvet, Durham DH1 3HP e-mail: [email protected] Tel: +44 0191 334 6107 http://etheses.dur.ac.uk ORGANIC AND HYDRIDE CHEMISTRY OF BERYLLIUM oy N.A. BELL. A thesis.submitted for the Degree of Doctor of Philosophy in the University- of Durham. June 196^-. I Acknowledgements. The author wishes to express his sincere thanks to Professor G-.E. Coates, M.A., D.Sc., F.R.I.C., under whose direction this research was carried out, for his constant encouragement and extremely valuable advice. ' The author is also indebted to the Department of Scien• tific and Industrial Research for a Research StudiSntshrp. I I Memorandum. The work described in this thesis was carried out in the University of Durham between September 19b1 and May 196A-. -
Chemistry 161 (350)
1 Chem261 MODULE 1: The Basics: Bonding and Molecular Structure The Structural Theory of Organic Chemistry - isomers: the important of structural formulas - the tetrahedral shape of methane - ionic bonds - covalent bonds Writing Lewis Structures Exceptions to the Octet Rule Formal Charge Summary of Formal Charges Resonance Summary of Rules for Resonance Quantum Mechanics Atomic Orbitals and Electron Configuration Molecular Orbitals The Structure Of Methane And Ethane: sp3 Hybridization The structure of Methane The Structure of Ethane The Structure of Ethene (Ethylene): sp2 Hybridization Restricted Rotation and the Double Bond Cis-Trans Isomerism The Structure of Ethyne (Acetylene): Sp Hybridization Bond Lengths of Ethylene, Ethene, and Ethane A Summary of Important Concepts that Come From Quantum Mechanics Molecular Geometry: The Valence Shell Electron Pair Repulsion Model - methane - ammonia - water - boron trifluoride - beryllium hydride - carbon dioxide How to interpret and Write Structural Formulas for cyclic and acyclic molecules - dash structural formulas - condensed structural formulas - bond-line formulas - three-dimensional formulas Text Sections: 1.2-1.17 Chapter1 Homework: 1.3, 1.5, 1.6, 1.7, 1.8, 1.9, 1.10, 1.11, 1.13, 1.14, 1.15, 1.16, 1.17, 1.18, 1.19, 1.20,1. 21, 1.22, 1.23, 1.24, 1.25, 1.27, 1.28, 1.29, 1.30, 1.31, 1.32, 1.33, 1.34, 1.35, 1.36, 1.37, 1.38, 1.39, 1.40, 1.41, 1.42, 1.43, 1.44, 1.45, 150 MODULE 2:Families of Carbon Compounds: Functional Groups, Intermolecular Forces, and Infrared (IR) Spectroscopy Hydrocarbons -
Ideal Gas Thermochemistry of Silicon Inorganic Organic and Ion Compounds
This is the peer reviewed version of the following article: Alexander Burcat, Elke Goos, Ideal gas thermochemical properties of silicon containing inorganic, organic compounds, radicals, and ions, Int J Chem Kinet. 2018;50:633–650, which has been published in final form at http://dx.doi.org/10.1002/kin.21188. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. 1 Ideal Gas Thermochemical Properties of Silicon containing Inorganic, Organic Compounds, Radicals and Ions. Alexander Burcat Faculty of Aerospace Engineering, Technion- Israel Institute of Technology, Haifa 32000, Israel, [email protected] and Elke Goos, Institute of Combustion Technology, Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR, German Aerospace Center), Pfaffenwaldring 38, 70569 Stuttgart, Germany. [email protected] ABSTRACT The ideal gas thermochemical properties such as standard heat of formation, entropy and heat capacities of 112 inorganic and 35 organic neutral compounds, radicals and ions containing silicon were calculated using molecular properties obtained with the G3B3 (or G3//B3LYP) method. Among them were linear and cyclic silanes, silenes, hydrocarbonsilanes, fluorine and oxygen containing compounds. Many of their molecular and thermodynamic properties were calculated for the first time and 16 of them had no CAS No. Additionally the thermochemical properties were presented in the NASA 7-term polynomial format for the temperature range of 200 K to 6000 K commonly used in chemical kinetic modeling and simulation programs. The polynomials are available in the supplement to this article free of charge. 2 KEYWORDS Thermodynamic data, Thermochemistry, Thermochemical properties, Heat of formation, Entropy, Enthalpy, Heat capacity, NASA format, Quantum chemical calculation, G3B3 composite approach, Silicon hydride, Silanes, Silicon fluoride, Silicon hydrocarbon, Silicon ions, Silicon compounds, Database INTRODUCTION Silicon containing substances are widely used and important for the mankind. -
Durham E-Theses
Durham E-Theses I. Some studies on Boronium salts; II. the coordination chemistry of Beryllium borohydride Banford, L. How to cite: Banford, L. (1965) I. Some studies on Boronium salts; II. the coordination chemistry of Beryllium borohydride, Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/9081/ Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in Durham E-Theses • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full Durham E-Theses policy for further details. Academic Support Oce, Durham University, University Oce, Old Elvet, Durham DH1 3HP e-mail: [email protected] Tel: +44 0191 334 6107 http://etheses.dur.ac.uk 2 I. Some Studies on Boronium Salts II. The Coordination Chemistry of Beryllium Borohydride by L. Banford. thesis submitted for the Degree of Doctor of Philosophy in the University of Durham. June 1963. ACKNOWLEDGEMENTS. The author wishes to express his sincere thanks to Professor G.E. Coates, M.A., D.Sc, F.E.I.C., under whose direction this research was carried out, for his constant encouragement and extremely valuable advice. The author is also indebted to the General Electric Company Limited for the award of a Research Scholarship.