Multi-configurational Quantum Chemistry on Quantum Computers

Multi-configurational Quantum Chemistry on Quantum Computers

Author: Kenji Sugisaki

Publisher:

Published: 2017

Total Pages:

ISBN-13:

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Quantum computing holds a prominent position in the current central science and technology. Among the diverse topics in the field of quantum computing, quantum chemical calculations of atoms and molecules have been intensively studied as the near-future applications of quantum computers. An approach to execute full-CI calculations on quantum computers by using quantum phase estimation algorithm was reported in 2005, and a quantum-classical hybrid computation model known as a variational quantum eigensolver was proposed in 2014. Most of theoretical methods for quantum chemical calculations on quantum computers reported so far assume that the approximate wave function having sufficiently large overlap with the full-CI wave function can be easily prepared. They sometimes assume that the Hartree-Fock wave function is a good approximation of the electronic ground state. However, when molecules have open shell low-spin characters like antiferromagnetically coupled multi-nuclear transition metal complexes and molecules undergoing covalent bond dissociations, the full-CI wave function possesses multi-configurational characters to satisfy the symmetry requirement of the spin operator S2, and the overlap between Hartree-Fock and full-CI wave functions becomes small. Development of theoretical methods to prepare good initial guess wave functions for open shell low-spin electronic structures on quantum computers without performing time-consuming computations is an important issue in quantum chemical calculations on quantum computers. Here we propose a method to construct multi-configurational wave functions having large overlap with the full-CI wave function on quantum computers, without performing any post-Hartree-Fock calculations [1]. The approach uses diradical characters obtainable from the occupation number of natural orbitals at the spin-projected UHF level as the measure of open shell characters. Quantum circuits for the preparation of the multi-configurational wave functions and some applications for electronic structure calculations will be given.


Multiconfigurational Quantum Chemistry

Multiconfigurational Quantum Chemistry

Author: Björn O. Roos

Publisher: John Wiley & Sons

Published: 2016-08-08

Total Pages: 240

ISBN-13: 0470633468

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The first book to aid in the understanding of multiconfigurational quantum chemistry, Multiconfigurational Quantum Chemistry demystifies a subject that has historically been considered difficult to learn. Accessible to any reader with a background in quantum mechanics and quantum chemistry, the book contains illustrative examples showing how these methods can be used in various areas of chemistry, such as chemical reactions in ground and excited states, transition metal and other heavy element systems. The authors detail the drawbacks and limitations of DFT and coupled-cluster based methods and offer alternative, wavefunction-based methods more suitable for smaller molecules.


Lecture Notes in Quantum Chemistry

Lecture Notes in Quantum Chemistry

Author: Björn O. Roos

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 417

ISBN-13: 3642581501

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"Quantum Chemistry" is the course material of a European Summer School in Quantum Chemistry, organized by Bj|rn O. Roos. It consists of lectures by outstanding scientists who participate in the education of students and young scientists. The book has a wider appeal as additional reading for University courses. Contents: P.-A. Malmquist: Mathematical Tools in Quantum Chemistry J. Olsen: The Method of Second Quantization P.R. Taylor: Molecular Symmetry and Quantum Chemistry B.O. Roos: The Multiconfigurational (MC) Self-Consistent Field (SCF) Theory P.E.M. Siegbahn: The Configuration Interaction Method T. Helgaker: Optimization of Minima and Saddle Points P.R. Taylor: Accurate Calculations and Calibration U. Wahlgren: Effective Core Potential Method


Quantum Chemistry and Dynamics of Excited States

Quantum Chemistry and Dynamics of Excited States

Author: Leticia González

Publisher: John Wiley & Sons

Published: 2021-02-01

Total Pages: 52

ISBN-13: 1119417759

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An introduction to the rapidly evolving methodology of electronic excited states For academic researchers, postdocs, graduate and undergraduate students, Quantum Chemistry and Dynamics of Excited States: Methods and Applications reports the most updated and accurate theoretical techniques to treat electronic excited states. From methods to deal with stationary calculations through time-dependent simulations of molecular systems, this book serves as a guide for beginners in the field and knowledge seekers alike. Taking into account the most recent theory developments and representative applications, it also covers the often-overlooked gap between theoretical and computational chemistry. An excellent reference for both researchers and students, Excited States provides essential knowledge on quantum chemistry, an in-depth overview of the latest developments, and theoretical techniques around the properties and nonadiabatic dynamics of chemical systems. Readers will learn: ● Essential theoretical techniques to describe the properties and dynamics of chemical systems ● Electronic Structure methods for stationary calculations ● Methods for electronic excited states from both a quantum chemical and time-dependent point of view ● A breakdown of the most recent developments in the past 30 years For those searching for a better understanding of excited states as they relate to chemistry, biochemistry, industrial chemistry, and beyond, Quantum Chemistry and Dynamics of Excited States provides a solid education in the necessary foundations and important theories of excited states in photochemistry and ultrafast phenomena.


Second Quantization-Based Methods in Quantum Chemistry

Second Quantization-Based Methods in Quantum Chemistry

Author: Poul Joergensen

Publisher: Elsevier

Published: 2012-12-02

Total Pages: 185

ISBN-13: 0323141099

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Second Quantization-Based Methods in Quantum Chemistry presents several modern quantum chemical tools that are being applied to electronic states of atoms and molecules. Organized into six chapters, the book emphasizes the quantum chemical methods whose developments and implementations have been presented in the language of second quantization. The opening chapter of the book examines the representation of the electronic Hamiltonian, other quantum-mechanical operators, and state vectors in the second-quantization language. This chapter also describes the unitary transformations among orthonormal orbitals in an especially convenient manner. In subsequent chapters, various tools of second quantization are used to describe many approximation techniques, such as Hartree-Fock, perturbation theory, configuration interaction, multiconfigurational Hartree-Fock, cluster methods, and Green’s function. This book is an invaluable source for researchers in quantum chemistry and for graduate-level students who have already taken introductory courses that cover the fundamentals of quantum mechanics through the Hartree-Fock method as applied to atoms and molecules.


New Methods in Computational Quantum Mechanics

New Methods in Computational Quantum Mechanics

Author: Ilya Prigogine

Publisher: John Wiley & Sons

Published: 2009-09-09

Total Pages: 812

ISBN-13: 0470142057

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The use of quantum chemistry for the quantitative prediction of molecular properties has long been frustrated by the technical difficulty of carrying out the needed computations. In the last decade there have been substantial advances in the formalism and computer hardware needed to carry out accurate calculations of molecular properties efficiently. These advances have been sufficient to make quantum chemical calculations a reliable tool for the quantitative interpretation of chemical phenomena and a guide to laboratory experiments. However, the success of these recent developments in computational quantum chemistry is not well known outside the community of practitioners. In order to make the larger community of chemical physicists aware of the current state of the subject, this self-contained volume of Advances in Chemical Physics surveys a number of the recent accomplishments in computational quantum chemistry. This stand-alone work presents the cutting edge of research in computational quantum mechanics. Supplemented with more than 150 illustrations, it provides evaluations of a broad range of methods, including: * Quantum Monte Carlo methods in chemistry * Monte Carlo methods for real-time path integration * The Redfield equation in condensed-phase quantum dynamics * Path-integral centroid methods in quantum statistical mechanics and dynamics * Multiconfigurational perturbation theory-applications in electronic spectroscopy * Electronic structure calculations for molecules containing transition metals * And more Contributors to New Methods in Computational Quantum Mechanics KERSTIN ANDERSSON, Department of Theoretical Chemistry, Chemical Center, Sweden DAVID M. CEPERLEY, National Center for Supercomputing Applications and Department of Physics, University of Illinois at Urbana-Champaign, Illinois MICHAEL A. COLLINS, Research School of Chemistry, Australian National University, Canberra, Australia REINHOLD EGGER, Fakultät für Physik, Universität Freiburg, Freiburg, Germany ANTHONY K. FELTS, Department of Chemistry, Columbia University, New York RICHARD A. FRIESNER, Department of Chemistry, Columbia University, New York MARKUS P. FÜLSCHER, Department of Theoretical Chemistry, Chemical Center, Sweden K. M. HO, Ames Laboratory and Department of Physics, Iowa State University, Ames, Iowa C. H. MAK, Department of Chemistry, University of Southern California, Los Angeles, California PER-ÅKE Malmqvist, Department of Theoretical Chemistry, Chemical Center, Sweden MANUELA MERCHán, Departamento de Química Física, Universitat de Valéncia, Spain LUBOS MITAS, National Center for Supercomputing Applications and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Illinois STEFANO OSS, Dipartimento di Fisica, Università di Trento and Istituto Nazionale di Fisica della Materia, Unità di Trento, Italy KRISTINE PIERLOOT, Department of Chemistry, University of Leuven, Belgium W. THOMAS POLLARD, Department of Chemistry, Columbia University, New York BJÖRN O. ROOS, Department of Theoretical Chemistry, Chemical Center, Sweden LUIS SERRANO-ANDRÉS, Department of Theoretical Chemistry, Chemical Center, Sweden PER E. M. SIEGBAHN, Department of Physics, University of Stockholm, Stockholm, Sweden WALTER THIEL, Institut für Organische Chemie, Universität Zürich, Zürich, Switzerland GREGORY A. VOTH, Department of Chemistry, University of Pennsylvania, Pennsylvania C. Z. Wang, Ames Laboratory and Department of Physi


Multiconfigurational Quantum Chemistry

Multiconfigurational Quantum Chemistry

Author: Björn O. Roos

Publisher: John Wiley & Sons

Published: 2016-08-03

Total Pages: 255

ISBN-13: 1119277884

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The first book to aid in the understanding of multiconfigurational quantum chemistry, Multiconfigurational Quantum Chemistry demystifies a subject that has historically been considered difficult to learn. Accessible to any reader with a background in quantum mechanics and quantum chemistry, the book contains illustrative examples showing how these methods can be used in various areas of chemistry, such as chemical reactions in ground and excited states, transition metal and other heavy element systems. The authors detail the drawbacks and limitations of DFT and coupled-cluster based methods and offer alternative, wavefunction-based methods more suitable for smaller molecules.


Theory and Applications of Computational Chemistry

Theory and Applications of Computational Chemistry

Author: Clifford Dykstra

Publisher: Elsevier

Published: 2011-10-13

Total Pages: 1336

ISBN-13: 0080456243

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Computational chemistry is a means of applying theoretical ideas using computers and a set of techniques for investigating chemical problems within which common questions vary from molecular geometry to the physical properties of substances. Theory and Applications of Computational Chemistry: The First Forty Years is a collection of articles on the emergence of computational chemistry. It shows the enormous breadth of theoretical and computational chemistry today and establishes how theory and computation have become increasingly linked as methodologies and technologies have advanced. Written by the pioneers in the field, the book presents historical perspectives and insights into the subject, and addresses new and current methods, as well as problems and applications in theoretical and computational chemistry. Easy to read and packed with personal insights, technical and classical information, this book provides the perfect introduction for graduate students beginning research in this area. It also provides very readable and useful reviews for theoretical chemists. * Written by well-known leading experts * Combines history, personal accounts, and theory to explain much of the field of theoretical and compuational chemistry * Is the perfect introduction to the field


New Methods in Computational Quantum Mechanics, Volume 93

New Methods in Computational Quantum Mechanics, Volume 93

Author: Ilya Prigogine

Publisher: Wiley-Interscience

Published: 1997-06-02

Total Pages: 0

ISBN-13: 9780471191278

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The use of quantum chemistry for the quantitative prediction of molecular properties has long been frustrated by the technical difficulty of carrying out the needed computations. In the last decade there have been substantial advances in the formalism and computer hardware needed to carry out accurate calculations of molecular properties efficiently. These advances have been sufficient to make quantum chemical calculations a reliable tool for the quantitative interpretation of chemical phenomena and a guide to laboratory experiments. However, the success of these recent developments is not well known outside the community of practitioners. In order to make the larger community of chemical physicists aware of the current state of the subject, this self-contained volume of Advances in Chemical Physics surveys a number of the recent accomplishments in computational quantum chemistry. Supplemented with more than 150 illustrations, this volume provides evaluations of a broad range of methods, including: Quantum Monte Carlo methods in chemistry Monte Carlo methods for real-time path integration The Redfield equation in condensed-phase quantum dynamics Multiconfigurational perturbation theory—applications in electronic spectroscopy Electronic structure calculations for molecules containing transition metals And more.