ADVANCES in the THEORY of QUANTUM SYSTEMS in CHEMISTRY and PHYSICS Progress in Theoretical Chemistry and Physics
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Arxiv:2011.07125V1 [Physics.Comp-Ph] 13 Nov 2020 Θ Hψθ I Θ Dx1
Better, Faster Fermionic Neural Networks James Spencery, David Pfauy, Aleksandar Botevy, W. M. C. Foulkes∗ yDeepMind, ∗Imperial College London London, UK {jamessspencer, pfau, botev}@google.com, [email protected] Abstract The Fermionic Neural Network (FermiNet) [12] is a recently-developed neural network architecture that can be used as a wavefunction Ansatz for many-electron systems, and has already demonstrated high accuracy on small systems. Here we present several improvements to the FermiNet that allow us to set new records for speed and accuracy on challenging systems. We find that increasing the size of the network is sufficient to reach chemical accuracy on atoms as large as argon. Through a combination of implementing FermiNet in JAX and simplifying several parts of the network, we are able to reduce the number of GPU hours needed to train the FermiNet on large systems by an order of magnitude. This enables us to run the FermiNet on the challenging transition of bicyclobutane to butadiene and compare against the PauliNet on the automerization of cyclobutadiene, and we achieve results near the state of the art for both. 1 Introduction Accurate computational solutions to the Schrödinger equation are critical for quantum chemistry and condensed matter physics. The time-independent form of the equation tries to solve for a wavefunction (x1; x2;:::; xn), which is an eigenfunction of the Hamiltonian, H^ of the system: H^ (x1;:::; xn) = E (x1;:::; xn) (1) H^ = − 1 P r2 + P 1 − P ZI + P ZI ZJ (2) 2 i i i>j jri−rj j iI jri−RI j I>J jRI −RJ j Here E is the real-valued energy of the wavefunction, xi (ri) is the position and spin (position) of the ith electron, RI is the position of the Ith nucleus and ZI is the charge of the Ith nucleus. -
This Manuscript Has Been Reproduced from the Microfilm Master
This manuscript has been reproduced from the microfilm master. UMI fi!ms the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectiaoning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6" x 9" black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. BeH & Howell Information and Learning 300 North Zeeb Road, Ann Arbor, MI 48106-1346 USA Dynamics of Harpooning Studied by Transition State Spectroscopy Andrew J. Hudson A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy. Graduate Department of Chemistry, in the University of Toronto. -
STIX 394372 1 En Bookfront
Quantum Systems in Physics, Chemistry, and Biology Progress in Theoretical Chemistry and Physics VOLUME 30 Honorary Editors Rudolph A. Marcus (California Institute of Technology, Pasadena, CA, USA) Roy McWeeny (Università di Pisa, Pisa, Italy) Editors-in-Chief J. Maruani (formerly Laboratoire de Chimie Physique, Paris, France) S. Wilson (formerly Rutherford Appleton Laboratory, Oxfordshire, UK) Editorial Board E. Brändas (University of Uppsala, Uppsala, Sweden) L. Cederbaum (Physikalisch-Chemisches Institut, Heidelberg, Germany) G. Delgado-Barrio (Instituto de Matemáticas y Física Fundamental, Madrid, Spain) E.K.U. Gross (Freie Universität, Berlin, Germany) K. Hirao (University of Tokyo, Tokyo, Japan) Chao-Ping Hsu (Institute of Chemistry, Academia Sinica, Taipei, Taiwan) R. Lefebvre (Université Pierre-et-Marie-Curie, Paris, France) R. Levine (Hebrew University of Jerusalem, Jerusalem, Israel) K. Lindenberg (University of California at San Diego, San Diego, CA, USA) A. Lund (University of Linköping, Linköping, Sweden) M.A.C. Nascimento (Instituto de Química, Rio de Janeiro, Brazil) P. Piecuch (Michigan State University, East Lansing, MI, USA) M. Quack (ETH Zürich, Zürich, Switzerland) S.D. Schwartz (Yeshiva University, Bronx, NY, USA) O. Vasyutinskii (Russian Academy of Sciences, St Petersburg, Russia) Y.A. Wang (University of British Columbia, Vancouver, BC, Canada) Former Editors and Editorial Board Members I. Prigogine (†) W.F. van Gunsteren (*) J. Rychlewski (†) H. Hubač (*) Y.G. Smeyers (†) E. Kryachko (*) R. Daudel (†) M.P. Levy (*) M. Mateev (†) G.L. Malli (*) W.N. Lipscomb (†) P.G. Mezey (*) Y. Chauvin (†) N. Rahman (*) H.W. Kroto (†) S. Suhai (*) H. Ågren (*) O. Tapia (*) V. Aquilanti (*) P.R. Taylor (*) D. Avnir (*) R.G. Woolley (*) J. Cioslowski (*) †: deceased; *: end of term More information about this series at http://www.springer.com/series/6464 Alia Tadjer ⋅ Rossen Pavlov (†) Jean Maruani ⋅ Erkki J. -
Los Premios Nobel De Química
Los premios Nobel de Química MATERIAL RECOPILADO POR: DULCE MARÍA DE ANDRÉS CABRERIZO Los premios Nobel de Química El campo de la Química que más premios ha recibido es el de la Quí- mica Orgánica. Frederick Sanger es el único laurea- do que ganó el premio en dos oca- siones, en 1958 y 1980. Otros dos también ganaron premios Nobel en otros campos: Marie Curie (física en El Premio Nobel de Química es entregado anual- 1903, química en 1911) y Linus Carl mente por la Academia Sueca a científicos que so- bresalen por sus contribuciones en el campo de la Pauling (química en 1954, paz en Física. 1962). Seis mujeres han ganado el Es uno de los cinco premios Nobel establecidos en premio: Marie Curie, Irène Joliot- el testamento de Alfred Nobel, en 1895, y que son dados a todos aquellos individuos que realizan Curie (1935), Dorothy Crowfoot Ho- contribuciones notables en la Química, la Física, la dgkin (1964), Ada Yonath (2009) y Literatura, la Paz y la Fisiología o Medicina. Emmanuelle Charpentier y Jennifer Según el testamento de Nobel, este reconocimien- to es administrado directamente por la Fundación Doudna (2020) Nobel y concedido por un comité conformado por Ha habido ocho años en los que no cinco miembros que son elegidos por la Real Aca- demia Sueca de las Ciencias. se entregó el premio Nobel de Quí- El primer Premio Nobel de Química fue otorgado mica, en algunas ocasiones por de- en 1901 al holandés Jacobus Henricus van't Hoff. clararse desierto y en otras por la Cada destinatario recibe una medalla, un diploma y situación de guerra mundial y el exi- un premio económico que ha variado a lo largo de los años. -
Better, Faster Fermionic Neural Networks
Better, Faster Fermionic Neural Networks James Spencery, David Pfauy, Aleksandar Botevy, W. M. C. Foulkes∗ yDeepMind, ∗Imperial College London London, UK {jamessspencer, pfau, botev}@google.com, [email protected] Abstract The Fermionic Neural Network (FermiNet) [12] is a recently-developed neural network architecture that can be used as a wavefunction Ansatz for many-electron systems, and has already demonstrated high accuracy on small systems. Here we present several improvements to the FermiNet that allow us to set new records for speed and accuracy on challenging systems. We find that increasing the size of the network is sufficient to reach chemical accuracy on atoms as large as argon. Through a combination of implementing FermiNet in JAX and simplifying several parts of the network, we are able to reduce the number of GPU hours needed to train the FermiNet on large systems by an order of magnitude. This enables us to run the FermiNet on the challenging transition of bicyclobutane to butadiene and compare against the PauliNet on the automerization of cyclobutadiene, and we achieve results near the state of the art for both. 1 Introduction Accurate computational solutions to the Schrödinger equation are critical for quantum chemistry and condensed matter physics. The time-independent form of the equation tries to solve for a wavefunction (x1; x2;:::; xn), which is an eigenfunction of the Hamiltonian, H^ of the system: H^ (x1;:::; xn) = E (x1;:::; xn) (1) H^ = − 1 P r2 + P 1 − P ZI + P ZI ZJ (2) 2 i i i>j jri−rj j iI jri−RI j I>J jRI −RJ j Here E is the real-valued energy of the wavefunction, xi (ri) is the position and spin (position) of the ith electron, RI is the position of the Ith nucleus and ZI is the charge of the Ith nucleus. -
Basic Research Needs for Catalysis Science
Basic Research Needs for Catalysis Science Report of the Basic Energy Sciences Workshop on Basic Research Needs for Catalysis Science to Transform Energy Technologies May 8–10, 2017 Image courtesy of Argonne National Laboratory. DISCLAIMER This report was prepared as an account of a workshop sponsored by the U.S. Department of Energy. Neither the United States Government nor any agency thereof, nor any of their employees or officers, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of document authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Copyrights to portions of this report (including graphics) are reserved by original copyright holders or their assignees, and are used by the Government’s license and by permission. Requests to use any images must be made to the provider identified in the image credits. This report is available in pdf format at https://science.energy.gov/bes/community-resources/reports/ REPORT OF THE BASIC RESEARCH NEEDS WORKSHOP FOR CATALYSIS SCIENCE Basic Research Needs for Catalysis Science TO TRANSFORM ENERGY TECHNOLOGIES Report from the U.S. Department of Energy, Office of Basic Energy Sciences Workshop May 8–10, 2017, in Gaithersburg, Maryland CHAIR: ASSOCIATE CHAIRS: Carl A. -
Metathesis: a "Change-Your-Partners" Dance Chemistry Nobel Prize - 2005
GENERAL I ARTICLE Metathesis: A "Change-Your-Partners" Dance Chemistry Nobel Prize - 2005 K Sivapriya and S Chandrasekaran On 5th October 2005, The Royal Swedish Academy of Sciences decided to award the Nobel Prize in Chemistry for 2005 jointly to Yves Chauvin, Institute ofFrench Petroleum, France, Robert H Grubbs, California Institute of Technol ogy, USA and Richard R Schrock, Massachusetts Institute K Sivapriya is interested in of Technology, USA for the development of the metathesis the design and development method in organic synthesis. This increasingly important of new and potent carbohy- organic process allows researchers to synthesize certain drate based glycosidase kinds of complex molecules that were previously difficult inhibitors, the study of and inefficient to make. Their research has opened the door enzyme mechanisms based on carbohydrate-protein to faster and more efficient methods for developing new interactions and to develop drugs and polymers. Imagination will soon be the only limit novel carbohydrate based to what molecules can be built in the laboratory! drugs. She also studies sulfur and selenium derived Introduction organic molecules in biological systems. Organic chemistry, the chemistry of carbon compounds, is a S Chandrasekaran's fascinating subject. The element carbon has a fantastic ability to research interests are form strong bonds with other carbon atoms to generate long development of new chains and rings. It can also bind to other elements like hydro synthetic methodologies, gen, oxygen, nitrogen, and sulfur, to form complex organic organometallic chemistry, synthesis of natural molecules. The versatility of carbon is critical in the formation products, catalysis and of many such molecules that are important for sustaining life on organic materials. -
In Li-FCH3 and Li-FH
Alkali-Metal Harpooning Reactions in Li-FCH3 and Li-FH A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy, Graduate Department of Chemistry, University of Toronto. @Copyright by HanBin Oh National Library Bib1iothèq.de nationaie du Canada Acquisitions and Acquisitions et Bibliographie Services services bibliographiques 395 Wellington Street 395, rue Wellington OttawaON K1AON4 Ottawa ON 'K1A ON4 Canada Canada The author has granted a non- L'auteur a accordé une licence non exclusive licence allowing the exc1wive pennettant à la National Lhrary of Canada to Bibliothèque nationale du Canada de reproduce, loan, distribute or sell reproduire, prêter, distribuer ou copies of this thesis in microfoxm, vendre des copies de cette thèse sous paper or electronic formats. la forme de microfichelfilm, de reproduction sur papier ou sur format électronique. The author retains ownership of the L'auteur conserve la propriété du copyright in this thesis. Neither the droit d'auteur qui protège cette thèse. thesis nor substantial extracts fkom it Ni la thèse ni des extraits substantiels may be printed or otherwise de celle-ci ne doivent être imprimés reproduced without the author's ou autrement reproduits sans son permission. autonsation. Thesis Abstract Alkali-Metal Harpooning Reactions in Li-FCH l3 and LieeFH HanE3in Oh For the degree of Doctor of Philosophy, Department of Chemisftry, University of Toronto 2ao 1 The van der Waals complexes, Lib4FCH3and Li..FH, have been forrned for the first time. using a laser-ablation method. The complexes were identified by photoionization tirne-of-fiight mass spectrometry. The excitation of the complexes accessed selected configura'tions of the Transition State (TS) of the electronically-excited reaction, ~i'(2p~~)+ XR -, LiX + R, leading thereafter to depletion of the complexes. -
Photoluminescence, Photophysics, and Photochemistry of the ${{\Rm{V}} {\Rm{B}}}^ -$ Defect in Hexagonal Boron Nitride
PHYSICAL REVIEW B 102, 144105 (2020) − Photoluminescence, photophysics, and photochemistry of the VB defect in hexagonal boron nitride Jeffrey R. Reimers ,1,2,* Jun Shen ,3,† Mehran Kianinia,2 Carlo Bradac ,2,4,‡ Igor Aharonovich,2 Michael J. Ford ,2,§ and Piotr Piecuch 3,5, 1International Centre for Quantum and Molecular Structures and Department of Physics, Shanghai University, Shanghai 200444, China 2University of Technology Sydney, School of Mathematical and Physical Sciences, Ultimo, New South Wales 2007, Australia 3Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA 4Department of Physics and Astronomy, Trent University, 1600 West Bank Dr., Peterborough, Ontario, Canada K9J 0G2 5Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA (Received 14 July 2020; revised 11 September 2020; accepted 15 September 2020; published 12 October 2020) − Extensive photochemical and spectroscopic properties of the VB defect in hexagonal boron nitride are calculated, concluding that the observed photoemission associated with recently observed optically detected 3 → 3 magnetic resonance is most likely of (1) E (1) A2 origin. Rapid intersystem crossing from the defect’s triplet to singlet manifolds explains the observed short excited-state lifetime and very low quantum yield. New experimental results reveal smaller intrinsic spectral bandwidths than previously recognized, interpreted in terms of spectral narrowing and zero-phonon-line shifting induced by the Jahn-Teller effect. Different types of computational methods are applied to map out the complex triplet and singlet defect manifolds, including the doubly ionized formulation of the equation-of-motion coupled-cluster theory that is designed to deal with the open-shell nature of defect states, and mixed quantum-mechanics/molecular-mechanics schemes enabling 5763-atom simulations. -
Yves Chauvin (1930–2015) Nobel-Prizewinning Chemist Who Rearranged Carbon–Carbon Bonds
OBITUARY COMMENT Yves Chauvin (1930–2015) Nobel-prizewinning chemist who rearranged carbon–carbon bonds. he impact of Yves Chauvin’s experiment, he reacted two types work across the chemi- of olefin (cyclic and non-cyclic) cal industries is mind- to show that the resulting prod- Tboggling. By dissecting how ucts combined fragments of both. carbon–carbon bonds shift in reac- He deduced that the molecular tions of petroleum compounds, swaps were not symmetrical, as Chauvin revealed the steps in one was commonly assumed, but were ALAIN JOCARD/AFP/GETTY of organic chemistry’s most impor- orchestrated by the formation of a tant reactions: metathesis. This temporary hydrocarbon ring con- Nobel-prizewinning work laid taining the metal catalyst. Other the path for chemical processes chemists, notably Robert Grubbs that are now used to make every- and Richard Schrock, with whom thing from pesticides to drugs. His Chauvin shared the 2005 Nobel proudest achievement, however, Prize in Chemistry, used this was developing crucial processes in insight to improve and develop the oil and plastics industries, now industrial reactions that under- used to produce millions of tonnes pin much of ‘green’ chemistry — of compounds each year. efficient industrial processes that Chauvin, who died on produce little waste. 27 January, was born in 1930 in When Chauvin retired from the Belgium, close to the border with IFP in 1995, he came to work in France. His French parents sent my surface organometallic chem- him across the border daily to istry laboratory at the University primary school; when his family of Lyon. He would regularly catch returned to France, Chauvin fin- the 5 a.m. -
Piotr Piecuch Department of Chemistry, Michigan State
NEW COUPLED-CLUSTER METHODS FOR MOLECULAR POTENTIAL ENERGY SURFACES: I. GROUND-STATE APPROACHES Piotr Piecuch Department of Chemistry, Michigan State University, East Lansing, Michigan 48824 P. Piecuch and K. Kowalski, in: Computational Chemistry: Reviews of Current Trends, edited by J. Leszczynski´ (World Scientific, Singapore, 2000), Vol. 5, pp. 1-104; K. Kowalski and P. Piecuch, J. Chem. Phys. 113, 18-35 (2000); 113, 5644-5652 (2000); J. Molec. Struct.: THEOCHEM 547, 191-208 (2001); Chem. Phys. Lett. 344, 165-175 (2001); P. Piecuch, S.A. Kucharski, and K. Kowalski, Chem. Phys. Lett. 344, 176-184 (2001); P. Piecuch, S.A. Kucharski, V. Spirkˇ o, and K. Kowalski, J. Chem. Phys. 115, 5796-5804 (2001); P. Piecuch, K. Kowalski, and I.S.O. Pimienta, Int. J. Mol. Sci., submitted (2001); P. Piecuch and K. Kowalski, Int. J. Mol. Sci., submitted (2001); K. Kowalski and P. Piecuch, J. Chem. Phys. 115, 2966-2978 (2001); P. Piecuch, K. Kowalski, I.S.O. Pimienta, and S.A. Kucharski, in: Accurate Description of Low-Lying Electronic States and Potential Energy Surfaces, ACS Symposium Series, Vol. XXX, edited by M.R. Hoffmann and K.G. Dyall (ACS, Washington, D.C., 2002), pp. XXX-XXXX; K. Kowalski and P. Piecuch, J. Chem. Phys., submitted (2001); P. Piecuch, S.A. Kucharski, and V. Spirkˇ o, J. Chem. Phys. 111, 6679-6692 (1999); K. Kowalski and P. Piecuch, J. Chem. Phys. 113, 8490-8502 (2000); 115, 643-651 (2001); K. Kowalski and P. Piecuch, Chem. Phys. Lett. 347, 237-246 (2001). 1 The \holy grail" of the ab initio electronic structure theory: The development of simple, \black-box," and affordable methods that can pro- vide highly accurate ( spectroscopic) description of ENTIRE GROUND- AND ∼ EXCITED-STATE POTENTIAL ENERGY SURFACES 14000 12000 10 NaF+H 10000 8 8000 V/cm-1 6000 6 Na *+ FH 4000 Energy/eV 4 2000 Na . -
Piotr Piecuch Department of Chemistry, Michigan State
NEW COUPLED-CLUSTER METHODS FOR MOLECULAR POTENTIAL ENERGY SURFACES: II. EXCITED-STATE APPROACHES Piotr Piecuch Department of Chemistry, Michigan State University, East Lansing, Michigan 48824 P. Piecuch and K. Kowalski, in: Computational Chemistry: Reviews of Current Trends, edited by J. Leszczynski´ (World Scientific, Singapore, 2000), Vol. 5, pp. 1-104; K. Kowalski and P. Piecuch, J. Chem. Phys. 113, 18-35 (2000); 113, 5644-5652 (2000); J. Molec. Struct.: THEOCHEM 547, 191-208 (2001); Chem. Phys. Lett. 344, 165-175 (2001); P. Piecuch, S.A. Kucharski, and K. Kowalski, Chem. Phys. Lett. 344, 176-184 (2001); P. Piecuch, S.A. Kucharski, V. Spirkˇ o, and K. Kowalski, J. Chem. Phys. 115, 5796-5804 (2001); P. Piecuch, K. Kowalski, and I.S.O. Pimienta, Int. J. Mol. Sci., submitted (2001); P. Piecuch and K. Kowalski, Int. J. Mol. Sci., submitted (2001); K. Kowalski and P. Piecuch, J. Chem. Phys. 115, 2966-2978 (2001); P. Piecuch, K. Kowalski, I.S.O. Pimienta, and S.A. Kucharski, in: Accurate Description of Low-Lying Electronic States and Potential Energy Surfaces, ACS Symposium Series, Vol. XXX, edited by M.R. Hoffmann and K.G. Dyall (ACS, Washington, D.C., 2002), pp. XXX-XXXX; K. Kowalski and P. Piecuch, J. Chem. Phys., submitted (2001); P. Piecuch, S.A. Kucharski, and V. Spirkˇ o, J. Chem. Phys. 111, 6679-6692 (1999); K. Kowalski and P. Piecuch, J. Chem. Phys. 113, 8490-8502 (2000); 115, 643-651 (2001); K. Kowalski and P. Piecuch, Chem. Phys. Lett. 347, 237-246 (2001). 1 The \holy grail" of the ab initio electronic structure theory: The development of simple, \black-box," and affordable methods that can pro- vide highly accurate ( spectroscopic) description of ENTIRE GROUND- AND ∼ EXCITED-STATE POTENTIAL ENERGY SURFACES 14000 12000 10 NaF+H 10000 8 8000 V/cm-1 6000 6 Na *+ FH 4000 Energy/eV 4 2000 Na .