University of Central Florida STARS Electronic Theses and Dissertations, 2004-2019 2007 Two-photon 3d Optical Data Storage Via Fluorescence Modulation Of Fluorene Dyes By Photochromic Diarylethenes Claudia Corredor University of Central Florida Part of the Chemistry Commons Find similar works at: https://stars.library.ucf.edu/etd University of Central Florida Libraries http://library.ucf.edu This Doctoral Dissertation (Open Access) is brought to you for free and open access by STARS. It has been accepted for inclusion in Electronic Theses and Dissertations, 2004-2019 by an authorized administrator of STARS. For more information, please contact [email protected]. STARS Citation Corredor, Claudia, "Two-photon 3d Optical Data Storage Via Fluorescence Modulation Of Fluorene Dyes By Photochromic Diarylethenes" (2007). Electronic Theses and Dissertations, 2004-2019. 3122. https://stars.library.ucf.edu/etd/3122 TWO-PHOTON 3D OPTICAL DATA STORAGE VIA FLUORESCENCE MODULATION OF FLUORENE DYES BY PHOTOCHROMIC DIARYLETHENES by CLAUDIA C. CORREDOR B.S. Universidad Nacional de Colombia, 1994 M. S. University of Central Florida, 2003 A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Chemistry in the College of Sciences at the University of Central Florida Orlando, Florida Spring Term 2007 Major Advisor: Kevin D. Belfield © 2007 Claudia C. Corredor ii ABSTRACT Three-dimensional (3D) optical data storage based on two-photon processes provides highly confined excitation in a recording medium and a mechanism for writing and reading data with less cross talk between multiple memory layers, due to the quadratic dependence of two- photon absorption (2PA) on the incident light intensity. The capacity for highly confined excitation and intrinsic 3D resolution affords immense information storage capacity (up to 1012 bits/cm3). Recently, the use of photochromic materials for 3D memory has received intense interest because of several major advantages over current optical systems, including their erasable/rewritable capability, high resolution, and high sensitivity. This work demonstrates a novel two-photon 3D optical storage system based on the modulation of the fluorescence emission of a highly efficient two-photon absorbing fluorescent dye (fluorene derivative) and a photochromic compound (diarylethene). The feasibility of using efficient intermolecular Förster Resonance Energy Transfer (RET) from the non-covalently linked two-photon absorbing fluorescent fluorene derivative to the photochromic diarylethene as a novel read-out method in a two-photon optical data storage system was explored. For the purpose of the development of this novel two-photon 3D optical storage system, linear and two-photon spectroscopic characterization of commercial diarylethenes in solution and in a polymer film and evidence of their cyclization (O→C) and cycloreversion (C→O) reactions induced by two-photon excitation were undertaken. iii For the development of a readout method, Resonance Energy Transfer (RET) from two- photon absorbing fluorene derivatives to photochromic compounds was investigated under one- and two-photon excitation. The Förster’s distances and critical acceptor concentrations were determined for non-bound donor-acceptor pairs in homogeneous molecular ensembles. To the best of my knowledge, modulation of the two-photon fluorescence emission of a dye by a photochromic diarylethene has not been reported as a mechanism to read the recorded information in a 3D optical data storage system. This system was demonstrated to be highly stable and suitable for recording data in thick storage media. The proposed RET-based readout method proved to be non-destructive (exhibiting a loss of the initial fluorescence emission less than 20% of the initial emission after 10,000 readout cycles). Potential application of this system in a rewritable-erasable optical data storage system was proved. As part of the strategy for the development of diarylethenes optimized for 3D optical data storage, derivatives containing π-conjugated fluorene molecules were synthesized and characterized. The final part of this reasearch demonstrated the photostability of fluorene derivatives showing strong molecular polarizability and high fluorescence quantum yields. These compounds are quite promising for application in RET-based two-photon 3D optical data storage. Hence, the photostability of these fluorene derivatives is a key parameter to establish, and facilitates their full utility in critical applications. iv To Celmira Martinez and Alonso Corredor- my guide To Luz, Alvaro, Daniel and Elisa Corena and Lina Corredor- my pride and joy To Martin Nunez- my soulmate To Guillermo Anzola- my inspiration v ACKNOWLEDGMENTS I would like to thank my advisor, Dr. Kevin D. Belfield, for his wise advice and guidance. I am deeply indebted for his personal support during good times and difficult times. I appreciate his nomination to the Graduate Student Summer Research Fellowship at UCF and the Summer Research Scholarships that gave me economic support during the months that I did not teach. It was a great pleasure to be part of the photochemistry, polymer, organic and materials chemistry Group at UCF. I enjoyed working with my lab-coworker and best friend Alma Morales including numerous passionate discussions and continuous exchange of ideas. I am thankful to present and past group members Sheng Yao, Katherine J. Schafer-Hales, Ciceron Yanez, Carolina Andrade, Shilong Bao, Stephen Andrasik, Sanchita Biswas, Mohammed Daoudi, Dao Nguyen, Mykhailo V. Bondar, Zhenli-Huang, Gheorge Luchita, for a friendly collaborative atmosphere. This dissertation was the result of a truly interdisciplinary and collaborative effort. I want to express my sincere thanks to Alma Morales and Sheg Yao for providing me the fluorene derivatives studied in this dissertation. I am deeply indebted to Mykhailo V. Bondar from whom I learned a lot. His way of explaining complicated concepts in an understandable manner is remarkable. It was him who helped me with photophysical experiments and did experimental work on the two-photon absorption measurements. I am going to miss his coffee breaks. Thank you, Mike! vi I also thank Zhenli-Huang for his efforts on refining and updating the two-photon laser scanning microscope for our 3D data storage experiments and for his work in 3D data storage and imaging simulations. I would like to thank F. E. Hernandez and I. Cohanoschi at the Plasmonic and Materials Design Laboratory at UCF for Z-scan experimental data on diarylethene 2 and for fruitful discussions. Especial thanks to Michael Sigman at the Forensic Trace Analysis Laboratory at UCF for their collaboration in the analysis of photoproducts of fluorene derivatives by HPLC-MS. All the collaborations have truly been rewarding and contributed to the interdisciplinary nature of this work. I wish to thank the Bristol-Myers Squibb Pharmaceutical Research Institute for its generous Doctorate Fellowship. Without the BMS support it would had been imposible to return to UCF to finish my degree. Thank you very much for giving me the time and the economic support that I needed. I would like to thank past and present members of the Institute that believed in my potential: Paul Kurtulik, Joel Young, Mark Powell, Frank Tomasella, Tom Raglione, David K Lloyd and Ruben Lozano. vii TABLE OF CONTENTS LIST OF FIGURES ...................................................................................................................... xii LIST OF TABLES.....................................................................................................................xviii LIST OF ACRONYMS/ABBREVIATIONS.............................................................................. xix CHAPTER 1. INTRODUCTION ................................................................................................... 1 1.1 Research Objective ............................................................................................................... 3 1.2 Research Outline................................................................................................................... 5 CHAPTER 2. BACKGROUND ..................................................................................................... 6 2.1 Two-Photon Absorption and its Contribution to Recent Advances in High Density 3D Optical Data Storage................................................................................................................... 6 2.2 Diarylethenes for Applications in Two-Photon 3D Optical Data Storage.......................... 11 2.2.1 Nonlinear Properties of Diarylethenes......................................................................... 16 2.3 Read-Out Systems in Optical Data Storage: Applications of Förster Resonance Energy Transfer (RET).......................................................................................................................... 17 2.4 Nonlinear Optical Properties and Photostability of Fluorene Derivatives.......................... 21 CHAPTER 3. PHOTOPHYSICAL CHARACTERIZATION OF DIARYLETHENES UNDER ONE- AND TWO-PHOTON EXCITATION .............................................................................. 25 3.1 General Comment on Materials, Methods, and Instruments .............................................. 26 3.2 Spectral Characterization of Diarylethene 1....................................................................... 29 viii 3.2.1. Steady-State