Densifying Metal Hydrides with High Temperature and Pressure
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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. -
Thermodynamic Hydricity of Small Borane Clusters and Polyhedral Closo-Boranes
molecules Article Thermodynamic Hydricity of Small Borane Clusters y and Polyhedral closo-Boranes Igor E. Golub 1,* , Oleg A. Filippov 1 , Vasilisa A. Kulikova 1,2, Natalia V. Belkova 1 , Lina M. Epstein 1 and Elena S. Shubina 1,* 1 A. N. Nesmeyanov Institute of Organoelement Compounds and Russian Academy of Sciences (INEOS RAS), 28 Vavilova St, 119991 Moscow, Russia; [email protected] (O.A.F.); [email protected] (V.A.K.); [email protected] (N.V.B.); [email protected] (L.M.E.) 2 Faculty of Chemistry, M.V. Lomonosov Moscow State University, 1/3 Leninskiye Gory, 119991 Moscow, Russia * Correspondence: [email protected] (I.E.G.); [email protected] (E.S.S.) Dedicated to Professor Bohumil Štibr (1940-2020), who unfortunately passed away before he could reach the y age of 80, in the recognition of his outstanding contributions to boron chemistry. Academic Editors: Igor B. Sivaev, Narayan S. Hosmane and Bohumír Gr˝uner Received: 6 June 2020; Accepted: 23 June 2020; Published: 25 June 2020 MeCN Abstract: Thermodynamic hydricity (HDA ) determined as Gibbs free energy (DG◦[H]−) of the H− detachment reaction in acetonitrile (MeCN) was assessed for 144 small borane clusters (up 2 to 5 boron atoms), polyhedral closo-boranes dianions [BnHn] −, and their lithium salts Li2[BnHn] (n = 5–17) by DFT method [M06/6-311++G(d,p)] taking into account non-specific solvent effect (SMD MeCN model). Thermodynamic hydricity values of diborane B2H6 (HDA = 82.1 kcal/mol) and its 2 MeCN dianion [B2H6] − (HDA = 40.9 kcal/mol for Li2[B2H6]) can be selected as border points for the range of borane clusters’ reactivity. -
Catalytic, Thermal, Regioselective Functionalization of Alkanes and Arenes with Borane Reagents
ACS Symposium Series 885, Activation and Functionalization of C-H Bonds, Karen I. Goldberg and Alan S. Goldman, eds. 2004. CHAP TER 8 Catalytic, Thermal, Regioselective Functionalization of Alkanes and Arenes with Borane Reagents John F. Hartwig Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107 Work in the author’s group that has led to a regioselective catalytic borylation of alkanes at the terminal position is summarized. Early findings on the photochemical, stoichiometric functionalization of arenes and alkanes and the successful extension of this work to a catalytic functionalization of alkanes under photochemical conditions is presented first. The discovery of complexes that catalyze the functionalization of alkanes to terminal alkylboronate esters is then presented, along with mechanistic studies on these system and computational work on the stoichiometric reactions of isolated metal-boryl compounds with alkanes. Parallel results on the development of catalysts and a mechanistic understanding of the borylation of arenes under mild conditions to form arylboronate esters are also presented. © 2004 American Chemical Society 136 137 1. Introduction Although alkanes are considered among the least reactive organic molecules, alkanes do react with simple elemental reagents such as halogens and oxygen.1,2) Thus, the conversion of alkanes to functionalized molecules at low temperatures with control of selectivity and at low temperatures is a focus for development of catalytic processes.(3) In particular the conversion of an alkane to a product with a functional group at the terminal position has been a longstanding goal (eq. 1). Terminal alcohols such as n-butanol and terminal amines, such as hexamethylene diamine, are major commodity chemicals(4) that are produced from reactants several steps downstream from alkane feedstocks. -
New Generation Cadmium‑Free Quantum Dots for Biophotonics and Nanomedicine
This document is downloaded from DR‑NTU (https://dr.ntu.edu.sg) Nanyang Technological University, Singapore. New Generation Cadmium‑Free Quantum Dots for Biophotonics and Nanomedicine Xu, Gaixia; Zeng, Shuwen; Zhang, Butian; Swihart, Mark T.; Yong, Ken‑Tye; Prasad, Paras N. 2016 Xu, G., Zeng, S., Zhang, B., Swihart, M. T., Yong, K.‑T., & Prasad, P. N. (2016). New Generation Cadmium‑Free Quantum Dots for Biophotonics and Nanomedicine. Chemical Reviews, 116(19), 12234‑12327. https://hdl.handle.net/10356/83973 https://doi.org/10.1021/acs.chemrev.6b00290 © 2016 American Chemical Society. This is the author created version of a work that has been peer reviewed and accepted for publication by Chemical Reviews, American Chemical Society. It incorporates referee’s comments but changes resulting from the publishing process, such as copyediting, structural formatting, may not be reflected in this document. The published version is available at: [http://dx.doi.org/10.1021/acs.chemrev.6b00290]. Downloaded on 06 Oct 2021 00:28:06 SGT Page 1 of 288 Submitted to Chemical Reviews 1 2 3 4 5 6 New Generation Cadmium-Free Quantum Dots for 7 8 Biophotonics and Nanomedicine 9 10 11 12 13 14 Gaixia Xu1,5†, Shuwen Zeng2,5†, Butian Zhang2, Mark T. Swihart3*, 15 2* 4* 16 Ken-Tye Yong and Paras N. Prasad 17 18 19 20 1 21 Key Laboratory of Optoelectronics Devices and Systems of Ministry of Education/Guangdong 22 Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen, P. R. 23 China 24 2 25 School of Electrical and Electronic Engineering, -
Hazardous Laboratory Chemicals Disposal Guide
Third Edition HAZARDOUS LABORATORY CHEMICALS DISPOSAL GUIDE Third Edition HAZARDOUS LABORATORY CHEMICALS DISPOSAL GUIDE Margaret-Ann Armour LEWIS PUBLISHERS A CRC Press Company Boca Raton London New York Washington, D.C. This edition published in the Taylor & Francis e-Library, 2005. To purchase your own copy of this or any of Taylor & Francis or Routledge’s collection of thousands of eBooks please go to http://www.ebookstore.tandf.co.uk/. Library of Congress Cataloging-in-Publication Data Armour, M.A. (Margaret-Ann) Hazardous laboratory chemicals disposal guide/Margaret-Ann Armour.—3rd ed. p. cm. Includes bibliographical references. ISBN 1-56670-567-3 1. Chemical laboratories—Waste disposal. 2. Hazardous substances. I. Title. QD64.A76 2003 542′.89–dc21 2002043358 This book contains information obtained from authentic and highly regarded sources. Reprinted material is quoted with permission, and sources are indicated. A wide variety of references are listed. Reasonable efforts have been made to publish reliable data and information, but the authors and the publisher cannot assume responsibility for the validity of all materials or for the consequences of their use. Neither this book nor any part may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, microfilming, and recording, or by any information storage or retrieval system, without prior permission in writing from the publisher. The consent of CRC Press LLC does not extend to copying for general distribution, for promotion, for creating new works, or for resale. Specific permission must be obtained in writing from CRC Press LLC for such copying. Direct all inquiries to CRC Press LLC, 2000 N.W. -
Boranes in Organic Chemistry 2. Β-Aminoalkyl- and Β-Sulfanylalkylboranes in Organic Synthesis V.M
Eurasian ChemTech Journal 4 (2002) 153-167 Boranes in Organic Chemistry 2. β-Aminoalkyl- and β-sulfanylalkylboranes in organic synthesis V.M. Dembitsky1, G.A. Tolstikov2*, M. Srebnik1 1Department of Pharmaceutical Chemistry and Natural Products, School of Pharmacy, P.O. Box 12065, The Hebrew University of Jerusalem, Jerusalem 91120, Israel 2Novosibirsk Institute of Organic Chemistry SB RAS, 9, Lavrentieva Ave., Novosibirsk, 630090, Russia Abstract Problems on using of β-aminoalkyl- and β-sulfanylalkylboranes in organic synthesis are considered in this review. The synthesis of boron containing α-aminoacids by Curtius rearrangement draws attention. The use of β-aminoalkylboranes available by enamine hydroboration are described. Examples of enamine desamination with the formation of alkenes, aminoalcohols and their transfor- mations into allylic alcohol are presented. These conversions have been carried out on steroids and nitro- gen containing heterocyclic compounds. The dihydroboration of N-vinyl-carbamate and N-vinyl-urea have been described. Examples using nitrogen and oxygen containing boron derivatives for introduction of boron functions were presented. The route to borylhydrazones by hydroboration of enehydrazones was envisaged. The possibility of trialkylamine hydroboration was shown on indole alkaloids and 11-azatricyclo- [6.2.11,802,7]2,4,6,9-undecatetraene examples. The synthesis of β-sulfanyl-alkylboranes by various routes was described. The synthesis of boronic thioaminoacids was carried out by free radical thiilation of dialkyl-vinyl- boronates. Ethoxyacetylene has been shown smoothly added 1-ethylthioboracyclopentane. Derivatives of 1,4-thiaborinane were readily obtained by divinylboronate hydroboration. Dialkylvinylboronates react with mercaptoethanol with the formation of 1,5,2-oxathioborepane derivatives. Stereochemistry of thiavinyl esters hydroboration leading to stereoisomeric β-sulfanylalkylboranes are discussed. -
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. -
Chapter 13 Group 13 Elements
Chapter 13 Group 13 Elements Physical Properties Metals Halides, oxides, hydroxides, salts of oxoacids Compounds containing nitrogen Metal boride Electron deficient borane and carborane clusters: an introduction 1 Borax Boron Relative abundances of the group 13 elements in the Earth’s crust. http://www.astro.virginia.edu/class/oconnell/LBT/ Abundances of elements in the Earth’s crusts. 2 Production of aluminium in the US between 1960 and 2008. World production (estimated) and US consumption of gallium between 1980 and 2008 3 Uses of aluminium in the US in 2008 Uses of boron in the US in 2008 Some physical properties of the group 13 elements, M, and their ions. 4 Some physical properties of the group 13 elements, M, and their ions. (Continued) α Part of one layer of the infinite lattice of -rhombohedral boron, showing the B 12 - icosahedral building blocks which are covalently linked to give a rigid, infinite lattice. 5 B 12 B12 +12B B60 B84 = B 12 B12 B60 β The construction of the B 84 -unit, the main building block of the infinite lattice of - rhombohedral boron. (a) In the centre of the unit is a B 12 -icosahedron, and (b) to each of these 12, another boron atom is covalently bonded. (c) A B60 -cage is the outer ‘skin’ of the B 84 -unit. (d) The final B 84 -unit can be described in terms of covalently bonded sub-units (B 12 )(B 12 )(B 60 ). Neutral Group 13 Hydrides Molecular compounds – BnHm B2H6 Delocalized 3-center 2-electron B-H-B interactions 6 Selected reactions of B 2H6 and Ga 2H6 GaBH 6 Gas Phase Solid State Part of one chain of the polymeric structure of crystalline GaBH 6 (X-ray diffraction at 110 K) 7 Adducts of GaH 3 t Formation of adducts RH 2N•GaH 3 (R = Me, Bu) − [Al 2H6(THF) 2] [Al(BH 4)3] [Al(BH 4)4] 8 π The formation of partial -bonds in a trigonal planar BX 3 molecule Reaction of BX 3 with a Lewis base Boron Halide Clusters B4Cl 4 B8Cl 8 B9Br 9 The family of BnXn (X = Cl, Br, I) molecules possess cluster structures. -
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. -
UNIVERSITY of CALIFORNIA, IRVINE Transition Metal Complexes
UNIVERSITY OF CALIFORNIA, IRVINE Transition Metal Complexes of Modified Azaphosphatranes DISSERTATION submitted in partial satisfaction of the requirements for the degree of DOCTOR OF PHILOSOPHY in Chemistry by Zachary Thammavongsy Dissertation Committee: Professor Jenny Y. Yang, Chair Professor Andrew S. Borovik Professor William J. Evans 2019 © 2019 Zachary Thammavongsy DEDICATION For my mother, Kor, and my father, Vinai, who sacrificed their lives for me to live out mine. ii TABLE OF CONTENTS Page LIST OF FIGURES vii LIST OF TABLES xv LIST OF SCHEMES xvi LIST OF CHARTS xvii ACKNOWLEDGMENTS xviii CURRICULUM VITAE xix ABSTRACT OF THE DISSERTATION xxv INTRODUCTION 1 CHAPTER 1: The Electronic and Steric Tolman Parameters of Proazaphosphatranes: Synthesis, Characterization, and Measurements 12 1.1. Motivation and Specific Aims 13 1.2. Background 13 1.3. Results and Discussion 15 R 1.3.1. Synthesis and Structure of Ni(L )(CO)3 Complexes (1-4) 15 Me 1.3.2. Synthesis and Structure of Ni(L )2(CO)2 Complex (5) 18 R 1.3.3. Tolman Electronic Parameters and Cone Angles of Ni(L )(CO)3 Complexes (1-4) 21 1.4. Conclusion 23 1.5. Experimental Details 24 1.6. References 38 CHAPTER 2: Expanding the Denticity of Proazaphosphatrane: Ligand Synthesis 41 2.1. Motivation and Specific Aims 42 2.2. Background 43 2.3. Results and Discussion 43 2.3.1. Synthesis of Tri-Substituted Tris(2-aminoethyl)amines 43 2.3.2. Synthesis of Protonated Tri-Substituted Azaphosphatranes 44 2.3.3. Synthesis of Tri-Substituted Proazaphosphatranes 46 2.4. Conclusion 49 2.5. -
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. -
Preparations, Solution Composition, and Reactions of Complex Metal Hydrides and Ate Complexes of Zinc, Aluminum, and Copper a Th
PREPARATIONS, SOLUTION COMPOSITION, AND REACTIONS OF COMPLEX METAL HYDRIDES AND ATE COMPLEXES OF ZINC, ALUMINUM, AND COPPER A THESIS Presented to The Faculty of the Division of Graduate Studies By John Joseph Watkins In Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the School of Chemistry Georgia Institute of Technology April, 1977 PREPARATIONS, SOLUTION COMPOSITION, AND REACTIONS OF COMPLEX METAL HYDRIDES AND ATE COMPLEXES OF ZINC, ALUMINUM, AND COPPER Approved: Erlin^rbrovenstein, Jr., Chairman H. 0. House E. C. Ashby Date approved by Chairman £~^3c>l~l~f ii ACKNOWLEDGMENTS Many individuals and organizations have contributed to the successful completion of this thesis. The following acknowledgments are not complete, but I hope I have expressed my gratitude to the people and organizations upon whom I depended the most. The School of Chemistry supported my first three years of work by the award of an NSF fellowship. My last year of work was generously supported by the St. Regis Paper Company, who graciously gave me leave of absence with salary so that the requirements for this thesis could be completed. This stipend and tuition support of my work freed me to concentrate on research without the financial difficulties encountered by many graduate students. All the faculty and staff of the School of Chemistry supported my research. I particularly would like to recognize Professor W. M. Spicer, Professor J. A. Bertrand, Professor C. L. Liotta, Mr. Gerald O'Brien, and Mr. D. E. Lillie. Post-doctoral assistants and fellow graduate students who contributed to my experience at the Georgia Insti tute of Technology include Dr.