Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 1965 Studies in Molecular Spectroscopy; I. Excimer Fluorescence, II. Heavy-Atom Spin-Orbital Coupling Effect and IIi. The lecE tronic Spectra of Ferrocene. Fred Jewel Smith Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Smith, Fred Jewel, "Studies in Molecular Spectroscopy; I. Excimer Fluorescence, II. Heavy-Atom Spin-Orbital Coupling Effect and IIi. The Electronic Spectra of Ferrocene." (1965). LSU Historical Dissertations and Theses. 1092. https://digitalcommons.lsu.edu/gradschool_disstheses/1092 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. This dissertation has bssn microfilmed exactly as received 6 6 -7 4 8 SMITH, Fred Jewel, 1939- STUDIES IN MOLECULAR SPECTROSCOPY} I. EXCIMER FLUORESCENCE, II. HEAVY- ATOM SPIN-ORBITAL COUPLING EFFECT AND HI. THE ELECTRONIC SPECTRA OF FERROCENE. Louisiana State University, Ph.D., 1965 Chemistry, physical University Microfilms, Inc., Ann Arbor, Michigan STUDIES IN MOLECULAR SPECTROSCOPY; I. EXCIMER FLUORESCENCE, II. HEAVY-ATOM SPIN-ORBITAL COUPLING EFFECT AND III . THE ELECTRONIC SPECTRA OF FERROCENE A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Chemistry by Fred Jewel Smith B.A., University of Southern Mississippi, 1960 August, 1965 ACKNOWLEDGMENT The author wishes to express his sincere appreciation to Dr. S. P. McGlynn, under whose direction this work was performed, for his helpful guidance throughout the course of this investigation. The author is also Indebted to the rest of the faculty and graduate * students at Louisiana State University for many helpful suggestions and comments, and especially Andrew T. Armstrong for his assistance in computer programming the calculations of Part I. Considerable gratitude is also due his wife, Phyllis, for her patience and encouragement throughout this investigation, and for aid in the preparation of this manuscript. The author gratefully acknowledges financial support received from the Petroleum Research Fund of the American Chemical Society, The United States Atomic Energy Coimnission-Biology Branch, and the Dr. Charles E. Coates Memorial Fund of the L.S.U. Foundation donated by George H. Coates. i i TABLE OF CONTENTS PAGE ACKNOWLEDGMENTS........................................................................................................ 11 LIST OF TABLES....................................................................................................... v LIST OF FIGURES....................................................................................................... v l l l ABSTRACT...................................................................................................... Ix I. EXCIMER FLUORESCENCE................................................................................ 1 A. Exclmer Fluorescence of Naphthalene and Its derivatives ........................................................................... 1 1. Introduction .................................................................................. 1 2. Experimental and Results * .................................................. 4 3. Simple Molecular Exclton and Charge Resonance Concepts ....................................................... 5 4. Configuration Interaction between Molecular Exclton State and Charge Resonance States ............................................... 17 5. Energy of Exclmer Fluorescence ....................................... 21 6. C onclusions ..................................................................................... 28 B. Delayed Exclmer Fluorescence of P y re n e ................................................................................................... 30 1. I n tr o d u c t i o n ................................................................................. 30 2. Results and Discussion ......................................................... 30 C. The Mechanism of Delayed Exclmer Fluorescence ......................................................................................... 36 II. HEAVY-ATOM SPIN-ORBITAL COUPLING EFFECT ...................................... 41 1. I n tr o d u c t i o n ................................................................................. 41 a) A Primitive Model of Spin- Orbital Coupling ............................................................. 41 b) Heavy-Atom Effects of M olecules ............................ 48 2. Experimental ................................................................................. 50 3. Results and Discussion .......................................................... 53 4. Phosphorescence Spectra .......................................................... 63 5. Conclusions ...................................................................................... 6 7 ' i l l PAGE I I I . THE ELECTRONICSPECTRA OF FERROCENE.............................................. 69 1. Introduction ................................................................................... 69 2. Experimental .................................................................................... 69 3. R e s u lts .................................................................................................. 70 4* Discussion ........................................................................................ 76 5. C onclusions......................................................................................... 87 APPENDIX.......................................................................................................................... 89 SELECTED BIBLIOGRAPHY ................................................................................................. 100 VITA .........................................................................................................................................109 iv LIST OF TABLES TABLE PAGE I. Energy of Exclmer Fluorescence ................................................... 10 II. Exclmer Properties ............................................................................... 11 III . Comparison of Observed^L Stabilisation and *L Exclton Splitting .* ........................................................................... 13 IV. Simple Charge Resonance Energies ............................................... 14 V* Calculated Exclmer Energies for the Internuclear Distances at which the Calculated Energy of the B 3»~ State Equals the Experimentally Observed Exclmer Energy, Z=3.18 ....................................................................... 29 VI. Proportionality of the Intensity of Various Luminescence of Pyrene to Incident Excitation Intensity, I ........................................... 34 VII. Decay Lifetimes of Long-Lived Luminescences of Pyrene ...................................................................... 35 VIII. Quantum Yields and Mean Phosphorescence Lifetimes of a-Halonaphthalene and Naphthalene in Heavy-Atom Solvents ........................................... 34 IX. The Limits of Variation of the Intersystem Crossing Rate C o n sta n t ..................................................................... 60 X. Comparison of External and Internal Heavy- Atom E ffect ................................................................................................... 61 XI. Comparison of the Prediction of Case A and Case B .................................................................................................. 62 XII. Effect of Medium of the Frequency (0,0) of Phosphorescence ................................................... 66 v TABLE PAGE XV. The Vibrational Frequencies and Vibrational Analysis of System V ........................................... 82 XVI. The Vibrational Frequencies and Vibrational Analysis of System VI .......................................... 83 XVII. The Vibrational Frequencies and Vibrational Analysis of System VII ...................................... 84 XVIII. The Vibrational Frequencies and Vibrational Analysis of System V I I I ...................................... 85 XIX. The Vibrational Frequencies and Vibrational Analysis of System I X .......................................... 86 XX. Some Possible Cooling Systems for use with the Low Temperature C e ll .......................................... 96 XXI. Low Temperature G lasses .................................................................... 99 v i LIST OF FIGURES FIGURE PAGE 1. Potential Energy Diagram for Excimer Formation ..................................................................................... 3 2. Fluorescence Spectra of 1-methyl- naphthalene ..................................................................................... 7 3. Fluorescence Spectra of 1,2-Dimethyl- naphthalene ................................................................................................... 9 4. Plot of I-A Versus the Experimental Excimer Energies ....................................................................................