2019 Heavy Element Chemistry Principal Investigators' Meeting
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CHEM 250 (4 Credits): Reactions of Nucleophiles and Electrophiles (Reactivity 1)
CHEM 250 (4 credits): Reactions of Nucleophiles and Electrophiles (Reactivity 1): Description: This course investigates fundamental carbonyl reactivity (addition and substitution) in understanding organic, inorganic and biochemical processes. Some emphasis is placed on enthalpy, entropy and free energy as a basis of understanding reactivity. An understanding of chemical reactivity is based on principles of Lewis acidity and basicity. The formation, stability and reactivity of coordination complexes are included. Together, these topics lead to an understanding of biochemical pathways such as glycolysis. Enzyme regulation and inhibition is discussed in the context of thermodynamics and mechanisms. Various applications of modern multi-disciplinary research will be explored. Prerequisite: CHEM 125. Course Goals and Objectives: 1. Students will gain a qualitative understanding of thermodynamics. A. Students will develop a qualitative understanding of enthalpy and entropy. B. Students will predict the sign of an entropy change for chemical or physical processes. C. Students will understand entropy effects such as the chelate effect on chemical reactions. D. Students will use bond enthalpies or pKas to determine the enthalpy change for a reaction. E. Students will draw or interpret a reaction progress diagram. F. Students will apply the Principle of Microscopic Reversibility to understand reaction mechanisms. G. Students will use Gibbs free energy to relate enthalpy and entropy changes. H. Students will develop a qualitative understanding of progress toward equilibrium under physiological conditions (the difference between G and Go.) I. Students will understand coupled reactions and how this can be used to drive a non- spontaneous reaction toward products. J. Students will apply LeChatelier’s Principle to affect the position of anequilibrium by adding or removing reactants or products. -
Brief Guide to the Nomenclature of Organic Chemistry
1 Brief Guide to the Nomenclature of Table 1: Components of the substitutive name Organic Chemistry (4S,5E)-4,6-dichlorohept-5-en-2-one for K.-H. Hellwich (Germany), R. M. Hartshorn (New Zealand), CH3 Cl O A. Yerin (Russia), T. Damhus (Denmark), A. T. Hutton (South 4 2 Africa). E-mail: [email protected] Sponsoring body: Cl 6 CH 5 3 IUPAC Division of Chemical Nomenclature and Structure suffix for principal hept(a) parent (heptane) one Representation. characteristic group en(e) unsaturation ending chloro substituent prefix 1 INTRODUCTION di multiplicative prefix S E stereodescriptors CHEMISTRY The universal adoption of an agreed nomenclature is a key tool for 2 4 5 6 locants ( ) enclosing marks efficient communication in the chemical sciences, in industry and Multiplicative prefixes (Table 2) are used when more than one for regulations associated with import/export or health and safety. fragment of a particular kind is present in a structure. Which kind of REPRESENTATION The International Union of Pure and Applied Chemistry (IUPAC) multiplicative prefix is used depends on the complexity of the provides recommendations on many aspects of nomenclature.1 The APPLIED corresponding fragment – e.g. trichloro, but tris(chloromethyl). basics of organic nomenclature are summarized here, and there are companion documents on the nomenclature of inorganic2 and Table 2: Multiplicative prefixes for simple/complicated entities polymer3 chemistry, with hyperlinks to original documents. An No. Simple Complicated No. Simple Complicated AND overall -
Magnetism, Magnetic Properties, Magnetochemistry
Magnetism, Magnetic Properties, Magnetochemistry 1 Magnetism All matter is electronic Positive/negative charges - bound by Coulombic forces Result of electric field E between charges, electric dipole Electric and magnetic fields = the electromagnetic interaction (Oersted, Maxwell) Electric field = electric +/ charges, electric dipole Magnetic field ??No source?? No magnetic charges, N-S No magnetic monopole Magnetic field = motion of electric charges (electric current, atomic motions) Magnetic dipole – magnetic moment = i A [A m2] 2 Electromagnetic Fields 3 Magnetism Magnetic field = motion of electric charges • Macro - electric current • Micro - spin + orbital momentum Ampère 1822 Poisson model Magnetic dipole – magnetic (dipole) moment [A m2] i A 4 Ampere model Magnetism Microscopic explanation of source of magnetism = Fundamental quantum magnets Unpaired electrons = spins (Bohr 1913) Atomic building blocks (protons, neutrons and electrons = fermions) possess an intrinsic magnetic moment Relativistic quantum theory (P. Dirac 1928) SPIN (quantum property ~ rotation of charged particles) Spin (½ for all fermions) gives rise to a magnetic moment 5 Atomic Motions of Electric Charges The origins for the magnetic moment of a free atom Motions of Electric Charges: 1) The spins of the electrons S. Unpaired spins give a paramagnetic contribution. Paired spins give a diamagnetic contribution. 2) The orbital angular momentum L of the electrons about the nucleus, degenerate orbitals, paramagnetic contribution. The change in the orbital moment -
CHEMISTRY for the Bottom of the Periodic Table
http://cyclotron.tamu.edu CHEMISTRY for the Bottom of the Periodic Table Techniques to investigate chemical properties of superheavy elements lead to improved methods for separating heavy metals THE SCIENCE The chemical properties of superheavy element 113, nihonium, are almost completely unknown, so a team of researchers from the Cyclotron Institute at Texas A&M University and the Institut Pluridisciplinaire Hubert Curien in France are developing techniques that could be used to study this fleeting element. As part of that effort, they are comparing the properties of nihonium to the chemically similar elements indium and thallium; to do so, the team studied the separation of these two elements using a new class of designer molecules called ionic liquids. THE IMPACT Measuring the chemical properties of nihonium and other superheavy elements will increase our understanding of the principles that control the Periodic Table. Comparing the data from nihonium to results for similar elements, obtained using the team’s fast, efficient, single-step process, reveals trends that arise from the structure of the Periodic Table. This research could also lead to better methods of re- using indium, a metal that is part of flat-panel displays but not currently mined in the United States. The proposed mechanism of transfer. Thallium (Tl) bonds with chlorine (Cl) and moves into the ionic liquid (in blue). SUMMARY The distribution of indium and thallium between the aque- ous and organic phases is the key to understanding the PUBLICATIONS separation of these elements. An aqueous solution, con- E.E. Tereshatov, M. Yu. Boltoeva, V. Mazan, M.F. -
Nobel Lecture, 8 December 1981 by ROALD HOFFMANN Department of Chemistry, Cornell University, Ithaca, N.Y
BUILDING BRIDGES BETWEEN INORGANIC AND ORGANIC CHEMISTRY Nobel lecture, 8 December 1981 by ROALD HOFFMANN Department of Chemistry, Cornell University, Ithaca, N.Y. 14853 R. B. Woodward, a supreme patterner of chaos, was one of my teachers. I dedicate this lecture to him, for it is our collaboration on orbital symmetry conservation, the electronic factors which govern the course of chemical reac- tions, which is recognized by half of the 1981 Nobel Prize in Chemistry. From Woodward I learned much: the significance of the experimental stimulus to theory, the craft of constructing explanations, the importance of aesthetics in science. I will try to show you how these characteristics of chemical theory may be applied to the construction of conceptual bridges between inorganic and organic chemistry. FRAGMENTS Chains, rings, substituents - those are the building blocks of the marvelous edifice of modern organic chemistry. Any hydrocarbon may be constructed on paper from methyl groups, CH 3, methylenes, CH 2, methynes, CH, and carbon atoms, C. By substitution and the introduction of heteroatoms all of the skeletons and functional groupings imaginable, from ethane to tetrodotoxin, may be obtained. The last thirty years have witnessed a remarkable renaissance of inorganic chemistry, and the particular flowering of the field of transition metal organo- metallic chemistry. Scheme 1 shows a selection of some of the simpler creations of the laboratory in this rich and ever-growing field. Structures l-3 illustrate at a glance one remarkable feature of transition metal fragments. Here are three iron tricarbonyl complexes of organic moie- ties - cyclobutadiene, trimethylenemethane, an enol, hydroxybutadiene - which on their own would have little kinetic or thermodynamic stability. -
An Exhibition Celebrating Some of Scotland's Finest Female Scientists
An exhibition celebrating some of Scotland’s finest female scientists www.rse.org.uk All photographs © Ian Georgeson Photography The Royal Society of Edinburgh, Scotland’s National Academy, is Scottish Charity No. SC000470 28 29 As Scotland’s National Academy, the Royal Society of Edinburgh is proud to number amongst its Fellowship some of the most talented leaders, thinkers and practitioners working in Scotland today. In this exhibition, we have chosen to focus on and celebrate some of the exceptional women scientists within the Fellowship. Leaders and pioneers in their fi elds, they are at the vanguard of new ideas, new knowledge and new technologies which are shaping our understanding of the world, supporting a more sustainable use of resources and securing advances in health care. Some are from Scotland, others have chosen to base their research and make their homes here; all of them are making a positive contribution to society. When we approached the women to be part of this exhibition, we asked them Seven of the women featured why they chose to become scientists. The responses were varied and enlightening: for some it was always their dream or passion or they had been encouraged and were or are members of the inspired by family, friends and colleagues. For others, the desire to become a RSE Young Academy of scientist came later whilst studying at university and realising that, not only did Scotland. they enjoy and were good at science but, it was also a realistic career choice. And what a career choice! Throughout the exhibition, we gain a sense of what these women love about their life in science: the joy in discovering and learning new things; the satisfaction that comes from working in teams and collaborating with colleagues from a wide range of disciplines; the pleasure in supporting and nurturing talent; and the fulfi lment that comes from doing something which is They are: making a diff erence to people’s lives and the way in which they live. -
Copyrighted Material
1 INTRODUCTION 1.1 WHY STUDY ORGANOMETALLIC CHEMISTRY? Organometallic chemists try to understand how organic molecules or groups interact with compounds of the inorganic elements, chiefl y metals. These elements can be divided into the main group, consisting of the s and p blocks of the periodic table, and the transition elements of the d and f blocks. Main-group organometallics, such as n -BuLi and PhB(OH)2 , have proved so useful for organic synthesis that their leading characteristics are usually extensively covered in organic chemistry courses. Here, we look instead at the transition metals because their chemistry involves the intervention of d and f orbitals that bring into play reaction pathways not readily accessible elsewhere in the periodic table. While main-group organometallics are typically stoichiometric reagents, many of their transition metal analogs are most effective when they act as catalysts. Indeed, the expanding range of applications of catalysis is a COPYRIGHTEDmajor reason for the continued MATERIAL rising interest in organo- metallics. As late as 1975, the majority of organic syntheses had no recourse to transition metals at any stage; in contrast, they now very often appear, almost always as catalysts. Catalysis is also a central prin- ciple of Green Chemistry 1 because it helps avoid the waste formation, The Organometallic Chemistry of the Transition Metals, Sixth Edition. Robert H. Crabtree. © 2014 John Wiley & Sons, Inc. Published 2014 by John Wiley & Sons, Inc. 1 2 INTRODUCTION for example, of Mg salts from Grignard reactions, that tends to accom- pany the use of stoichiometric reagents. The fi eld thus occupies the borderland between organic and inorganic chemistry. -
IUPAC Wire See Also
News and information on IUPAC, its fellows, and member organizations. IUPAC Wire See also www.iupac.org Flerovium and Livermorium Join the Future Earth: Research for Global Periodic Table Sustainability n 30 May 2012, IUPAC officially approved he International Council for Science (ICSU), of the name flerovium, with symbol Fl, for the which IUPAC is a member, announced a new Oelement of atomic number 114 and the name T10-year initiative named Future Earth to unify livermorium, with symbol Lv, for the element of atomic and scale up ICSU-sponsored global environmental- number 116. The names and symbols were proposed change research. by the collaborating team of the Joint Institute for Nuclear Research (Dubna, Russia) and the Lawrence Operational in 2013, this new ICSU initiative will Livermore National Laboratory (Livermore, California, provide a cutting-edge platform to coordinate scien- USA) to whom the priority for the discovery of these tific research to respond to the most critical social and elements was assigned last year. The IUPAC recom- environmental challenges of the 21st century at global mendations presenting these names is to appear in and regional levels. “This initiative will link global envi- the July 2012 issue of Pure and Applied Chemistry. ronmental change and fundamental human develop- ment questions,” said Diana Liverman, co-director of The name flerovium, with symbol Fl, lies within the Institute of the Environment at the University of tradition and honors the Flerov Laboratory of Nuclear Arizona and co-chair of the team Reactions in Dubna, Russia, where the element of that is designing Future Earth. -
The Histories Hidden in the Periodic Table
The Histories Hidden in the Periodic Table From poisoned monks and nuclear bombs to the “transfermium wars,” mapping the atomic world hasn’t been easy. By Neima Jahromi 6:00 A.M. As element hunters have become element makers, the periodic table’s meaning has changed. It now describes what is possible, in addition to what merely exists. Illustration by Ilya Milstein The story of the fifteenth element began in Hamburg, in 1669. The unsuccessful glassblower and alchemist Hennig Brandt was trying to find the philosopher’s stone, a mythical substance that could turn base metals into gold. Instead, he distilled something new. It was foamy and, depending on the preparation, yellow or black. He called it “cold fire,” because it glowed in the dark. Interested parties took a look; some felt that they were in the presence of a miracle. “If anyone had rubbed himself all over with it,” one observer noted, “his whole figure would have shone, as once did that of Moses when he came down from Mt. Sinai.” Robert Boyle, the father of modern chemistry, put some on his hand and noted how “mild and innocent” it seemed. Another scientist saw particles in it twinkling “like little stars.” At first, no one could figure out what the Prometheus of Hamburg had stolen. After one of Brandt’s confidants provided a hint—the main ingredient was “somewhat that belong’d to the Body of Man”—Boyle deduced that he and his peers had been smearing themselves with processed urine. As the Cambridge chemist Peter Wothers explains in his new history of the elements, “Antimony, Gold, and Jupiter’s Wolf” (Oxford), Brandt’s recipe called for a ton of urine. -
Introduction to NMR Spectroscopy of Proteins
A brief introduction to NMR spectroscopy of proteins By Flemming M. Poulsen 2002 1 Introduction Nuclear magnetic resonance, NMR, and X-ray crystallography are the only two methods that can be applied to the study of three-dimensional molecular structures of proteins at atomic resolution. NMR spectroscopy is the only method that allows the determination of three-dimensional structures of proteins molecules in the solution phase. In addition NMR spectroscopy is a very useful method for the study of kinetic reactions and properties of proteins at the atomic level. In contrast to most other methods NMR spectroscopy studies chemical properties by studying individual nuclei. This is the power of the methods but sometimes also the weakness. NMR spectroscopy can be applied to structure determination by routine NMR techniques for proteins in the size range between 5 and 25 kDa. For many proteins in this size range structure determination is relatively easy, however there are many examples of structure determinations of proteins, which have failed due to problems of aggregation and dynamics and reduced solubility. It is the purpose of these notes to introduce the reader to descriptions and applications of the methods of NMR spectroscopy most commonly applied in scientific studies of biological macromolecules, in particular proteins. The figures 1,2 and 11 are copied from “Multidímensional NMR in Liquids” by F.J.M de Ven (1995)Wiley-VCH The Figure13 and Table 1 have been copied from “NMR of Proteins and Nucleic acis” K. Wüthrich (1986) Wiley Interscience The Figures 20, 21 and 22 have been copied from J. -
Inelastic Collisions of Atomic Thorium and Molecular Thorium Monoxide with Cold Helium-3
Inelastic collisions of atomic thorium and molecular thorium monoxide with cold helium-3 The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Au, Yat Shan. 2014. Inelastic collisions of atomic thorium and molecular thorium monoxide with cold helium-3. Doctoral dissertation, Harvard University. Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:12274226 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#LAA Inelastic Collisions of Atomic Thorium and Molecular Thorium Monoxide with Cold Helium-3 A dissertation presented by Yat Shan Au to The Department of Physics in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the subject of Physics Harvard University Cambridge, Massachusetts November 2013 c 2013 - Yat Shan Au All rights reserved. Dissertation advisor Author Professor John Morrissey Doyle Yat Shan Au Inelastic Collisions of Atomic Thorium and Molecular Thorium Monoxide with Cold Helium-3 Abstract We measure inelastic cross sections for atomic thorium (Th) and molecular thorium monoxide (ThO) in collisions with 3He at temperatures near 1 K. We determine the 3 −17 −2 Zeeman relaxation cross section for Th ( F2) to be ∼ 2 × 10 cm at 800 mK. 3 We study electronic inelastic processes in Th ( P0) and find no quenching even after 106 collisions at 800 mK. We measure the vibrational quenching cross section for ThO (X, ν = 1) to be (7:9 ± 2:7) × 10−19 cm−2 at 800 mK. -
Chapter 1: Atoms, Molecules and Ions
Previous Chapter Table of Contents Next Chapter Chapter 1: Atoms, Molecules and Ions Section 1.1: Introduction In this course, we will be studying matter, “the stuff things are made of”. There are many ways to classify matter. For instance, matter can be classified according to the phase, that is, the physical state a material is in. Depending on the pressure and the temperature, matter can exist in one of three phases (solid, liquid, or gas). The chemical structure of a material determines the range of temperatures and pressures under which this material is a solid, a liquid or a gas. Consider water for example. The principal differences between water in the solid, liquid and gas states are simply: 1) the average distance between the water molecules; small in the solid and the liquid and large in the gas and 2) whether the molecules are organized in an orderly three-dimensional array (solid) or not (liquid and gas). Another way to classify matter is to consider whether a substance is pure or not. So, matter can be classified as being either a pure substance or a mixture. A pure substance has unique composition and properties. For example, water is a pure substance (whether from Texas or Idaho, each water molecule always contains 2 atoms of hydrogen for 1 atom of oxygen). Under the same atmospheric pressure and at the same ambient temperature, water always has the same density. We can go a little further and classify mixtures are either homogeneous or heterogeneous. In a homogeneous mixture, for example, as a result of mixing a teaspoon of salt in a glass of water, the composition of the various components and their properties are the same throughout.