COMPUTATIONAL METHODS FOR LARGE MOLECULES AND LOCALIZED STATES IN SOLIDS

Transcription

1 COMPUTATIONAL METHODS FOR LARGE MOLECULES AND LOCALIZED STATES IN SOLIDS

2 THE IBM RESEARCH SYMPOSIA SERIES 1971: Computational Methods in Band Theory Editors: P.M. Marcus, J. F. Janak, and A.R. Williams 1972: Computational Solid State Physics Editors: F. Herman, N. W. Dalton, and T. R. Koehler 1972: Sparse Matrices and Their Applications Editors: D. J. Rose and R. A. Willoughby 1972: Complexity of Computer Computations Editors: R. E. Miller and J. W. Thatcher Associate Editor: J. D. Bohlinger 1973: Computational Methods for Large Molecules and Localized States in Solids Editors: F. Herman, A. D. McLean, and R. K. Nesbet

3 COMPUTATIONAL METHODS FOR LARGE MOLECULES AND LOCALIZED STATES IN SOLIDS Proceedings of a Symposium, Held May 15-17,1972, at the IBM Research Laboratory, San Jose, California Edited by F. Herman, A. D. McLean, and R. K. Nesbet Large-Scale Scientific Computations Department IBM Research Laboratory, San Jose, California ~ PLENUM PRESS NEW YORK-LONDON 1973

4 Library of Congress Catalog Card Number ISBN-13: e-isbn-13: DOl: / Plenum Press, New York Softcover reprint of the hardcover 1 st edition 1973 A Division of Plenum Publishing Corporation 227 West 17th Street, New York, N.Y United Kingdom edition published by Plenum Press, London A Division of Plenum Publishing Company, Ltd. Davis House (4th Floor), 8 Scrubs Lane, Harlesden, London, NW10 6SE, England All rights reserved No part of this publication may be reproduced in any form without written permission from the publisher

5 PREFACE During the past few years, there has been dramatic progress in theoretical and computational studies of large molecules and localized states in solids. Various semi-empirical and first-principles methods well known in quantum chemistry have been applied with considerable success to ever larger and more complex molecules, including some of biological importance, as well as to selected solid state problems involving localized electronic states. Increasingly, solid state physicists are adopting a molecular point of view in attempting to understand the nature of electronic states associated with (a) isolated structural and chemical defects in solids; (b) surfaces and interfaces; and (c) bulk disordered solids, most notably amorphous semiconductors. Moreover, many concepts and methods already widely used in solid state physics are being adapted to molecular problems. These adaptations include pseudopotentials, statistical exchange approximations, muffin-tin model potentials, and multiple scattering and cellular methods. In addition, many new approaches are being devised to deal with progressively more complex molecular and localized electronic state problems. In view of these developments, IBM San Jose Research Laboratory, in conjunction with IBM World Trade Corporation, organized a research symposium on the application of the computational methods of quantum chemistry and solid state physics to the study of electronic properties of complex molecules, localized imperfections in solids, and disordered condensed systems. Dr. Frank Herman served as Symposium Chairman. The present volume consists of papers presented at this symposium, which was held on May 15 to 17, 1972 at the IBM San Jose Research Laboratory. An important purpose of this symposium was to bring together active workers in theoretical chemistry and solid state theory for an exchange of ideas and methodology across the communication barrier that has traditionally separated these two disciplines. In both of these fields theoretical and computational methods have v

6 vi PREFACE reached a high level of sophistication, and most theoreticians, for natural reasons, normally work within the framework of only one of these disciplines. The organizers of this symposium believe that such meetings are essential for minimizing provincialism, for making people aware of techniques used in one area which may be ready for exploitation in another, and for exploring in depth the regions that overlap. The subject of provincialism in science is considered further in the Banquet Speech by Professor George S. Hammond. One of the highlights of the symposium was a panel discussion at which representatives of many different schools of thought presented their views and compared notes. This panel discussion is reproduced in the present volume. The papers included here address the following topics: (a) scientific goals and challenges for computational studies of complex molecules and localized states in solids; (b) effectiveness of different approaches to these goals; (c) discussion of relative accuracy and practicality of traditional methods of quantum chemistry; (d) potential applications of new computational methods directed specifically to complex molecules and localized states in solids; (e) discussion of areas of research requiring a synthesis of molecular and solid state concepts, for example, exciton states in molecular crystals, biological macromolecules, polymers, molecules in crystalline environments, localized defects in crystals, surface states, and localized states in disordered solids. The organizers of this symposium are indebted to many persons who have contributed to its success. We are particularly grateful to Dr. Andrew H. Eschenfelder, IBM San Jose Research Laboratory and Mr. G~ry S. Kozak, IBM World Trade Headquarters, New York for their encouragement and financial support; and Mr. Warren C. Edwards, IBM San Jose Research Laboratory, for his expert handling of the local arrangements. We are also grateful to many of our colleagues within the IBM World Trade Corporation for their cooperation in bringing selected speakers and participants to the symposium. We are particularly grateful to the following: Mr. P. de Blanpre, IBM France; Mr. L. O. Bunk a, IBM Canada; Mr. O. Cilius-Nielsen, IBM Denmark; Mr. F. G. Insinger and Mr. J. A. van der Pool, IBM Netherlands; Mr. R. Jacqmin, IBM Belgium; Mr. J. S. Nist, IBM Mexico; Mr. J. J. Peppercorn. ~r.

7 PREFACE S. Quigley, and Mr. C. Squire, IBM United Kingdom; Dr. P. Schweitzer, IBM Germany; Mr. A. Serrano, IBM Spain; Dr. J. Vogel, IBM Switzerland; and Mr. G. Wethal, IBM Norway. We are also indebted to Drs. William J. Turner and Bernard J. van der Hoeven, IBM Research, Yorktown Heights for administrative support; and Mr. Robert N. Ubell, President, Plenum Publishing Corporation, for his cooperation. Finally, we are indebted to many of our colleagues at IBM San Jose Research Laboratory for their important contributions. In particular, thanks are due to Miss Colleen de Long, Mrs. Linda Lopez, Mrs. Jacqueline Mendenhall, and Mrs. Patricia B. Rodgers for extensive typing and editorial assistance; Mrs. Rodgers again for transcribing the tape recordings of the symposium; Mr. Jack De Lany, Mr. Brad Hall, and Mrs. Lorraine Riddle for artistic and graphics support; and Mr. Rick W. Kipp, Mr. Rudy M. Martinez and Mr. Donald E. Schreiber for help with the visual aids. This effort can be considered a success if the symposium and the present volume help to open up channels of communication between quantum chemists and theoretical solid state physicists. Frank Herman, A. D. McLean, and R. K. Nesbet Symposium Proceedings Coeditors

8 CONTENTS WELCOMING REMARKS A. H. Eschenfelder 1 1. Scientific Challenges I INTRODUCTORY REMARKS R. S. Mulliken 5 QUANTUM CHEMISTRY. THEORY OF GEOMETRIES AND ENERGIES OF SMALL MOLECULES J. A. Pople ORGANIC TRANSITION STATES L. Salem SOLID STATE CONCEPTS IN RADIATION CHEMISTRY AND BIOLOGY G. W. Robinson MOLECULAR MODELING BY COMPUTER W. A. Little 2. Scientific Challenges II INTRODUCTORY REMARKS J. A. Barker 57 STRUCTURAL CHARACTERISTICS AND ELECTRONIC STATES OF HEMOGLOBIN M. Weissbluth MOLECULAR THEORY OF NUCLEATION... J. W. Corbett, H. L. Frisch, D. Peak and M. St. Peters 67 ix

9 x CONTENTS 3. Computational Methods I APPROXIMATIONS FOR LARGE-MOLECULE CALCULATIONS F. E. Harris AB INITIO COMPUTATION OF MOLECULAR STRUCTURES THROUGH CONFIGURATION INTERACTION P. S. Bagus, B. Liu, A. D. McLean and M. Yoshimine APPROXIMATE METHODS IN QUANTUM CHEMISTRY M. C. Zerner LCAO-MO CLUSTER MODEL FOR LOCALIZED STATES IN COVALENT SOLIDS G. D. Watkins and R. P. Messmer DESCRIPTION OF MOLECULES IN TERMS OF LOCALIZED ORBITALS K. Ruedenberg Computational Methods II INTRODUCTORY REMARKS P. S. Bagus THE SCF-Xa SCATTERED-WAVE METHOD..... K. H. Johnson, J. G. Norman, Jr., and J.W.D. Connolly THE ORBITAL CORRECTION METHOD W. A. Harrison PANEL DISCUSSION ON COMPUTATIONAL METHODS... Panel Members: P. S. Bagus, F. E. Harris, W. A. Harrison, K. H. Johnson, A. D. McLean, U. T. Mueller-Westerhoff, K. Ruedenberg, G. A. Segal, H. S. Taylor, G. D. Watkins, and M. C. Zerner Discussion from Floor: T. L. Gilbert, R. K. Nesbet, J. A. Pople, and L. Salem AB INITIO SCF CALCULATIONS OF THE CARBAZOLE AND 2,4,7-TRINITRO-9-FLUORENONE (TNF) MOLECULES I. P. Batra and H. Seki

10 CONTENTS xi 5. Localized States and Disordered Solids I SURFACE STATES AND LEED.. P. M. Marcus and D. W. Jepsen WANNIER FUNCTIONS W. Kohn DEVELOPMENTS IN LOCALIZED PSEUDOPOTENTIAL METHODS P. W. Anderson and J. D. Weeks LOCALIZED DEFECTS IN SEMICONDUCTORS F. L. Vook and K. L. Brower TRANSMISSION OF ELECTRONS THROUGH A DISORDERED ARRAY OF POTENTIALS P. Erd8s and R. C. Herndon Localized States and Disordered Solids II INTRODUCTORY REMARKS D. Henderson ELECTRONIC STRUCTURE OF AMORPHOUS SEMICONDUCTORS D. Weaire and M. F. Thorpe SOME POLYTYPES OF GERMANIUM AND A TIGHT BINDING MODEL FOR THE ELECTRONIC STRUCTURE OF AMORPHOUS SOLIDS D. Henderson and I. B. Ortenburger COEXISTENCE OF LOCALIZED AND EXTENDED STATES? S. Kirkpatrick and T. P. Eggarter CLUSTER SCATTERING IN AMORPHOUS SEMICONDUCTORS AND LIQUID METALS J. Keller PROPERTIES OF LOCALIZED STATES IN DISORDERED MATERIALS K. F. Freed 7. Banquet Speech ARE THERE CULTS OF THEORETICIANS? G. S. Hammond

11 xii CONTENTS 8. Symposium Summary SUMMARY AND CONCLUDING REMARKS R. K. Nesbet List of Contributors Subject Index