Phosphorus and Sulfur Cosmochemistry: Implications for the Origins of Life
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Phosphorus and Sulfur Cosmochemistry: Implications for the Origins of Life Item Type text; Electronic Dissertation Authors Pasek, Matthew Adam Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 07/10/2021 06:16:37 Link to Item http://hdl.handle.net/10150/194288 PHOSPHORUS AND SULFUR COSMOCHEMISTRY: IMPLICATIONS FOR THE ORIGINS OF LIFE by Matthew Adam Pasek ________________________ A Dissertation Submitted to the Faculty of the DEPARTMENT OF PLANETARY SCIENCE In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY In the Graduate College UNIVERSITY OF ARIZONA 2 0 0 6 2 THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE As members of the Dissertation Committee, we certify that we have read the dissertation prepared by Matthew Adam Pasek entitled Phosphorus and Sulfur Cosmochemistry: Implications for the Origins of Life and recommend that it be accepted as fulfilling the dissertation requirement for the Degree of Doctor of Philosophy _______________________________________________________________________ Date: 04/11/2006 Dante Lauretta _______________________________________________________________________ Date: 04/11/2006 Timothy Swindle _______________________________________________________________________ Date: 04/11/2006 Alexander Pavlov _______________________________________________________________________ Date: 04/11/2006 Neville Woolf _______________________________________________________________________ Date: 04/11/2006 William Boynton Final approval and acceptance of this dissertation is contingent upon the candidate’s submission of the final copies of the dissertation to the Graduate College. I hereby certify that I have read this dissertation prepared under my direction and recommend that it be accepted as fulfilling the dissertation requirement. ________________________________________________ Date: 04/11/2006 Dissertation Director: Dante Lauretta 3 STATEMENT BY AUTHOR This dissertation has been submitted in partial fulfillment of requirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this dissertation are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his or her judgment the proposed use of the material is in the interests of scholarship. In all other instances, however, permission must be obtained from the author. SIGNED: ________________________________ Matthew Adam Pasek 4 ACKNOWLEDGEMENTS The author thanks his wonderful wife Virginia for her patience and understanding during the course of this research and writing of this dissertation. Virginia also assisted in edits of the document, preparation of a few figures, and provided much needed encouragement. I look forward to taking you to Hawai’i! The author also thanks Hansen’s Soda Company for their creation of the Monster Energy Drink, without which this dissertation would never have been completed. Unleash the Beast indeed. The author also thanks his parents for nurturing his scientific development, and for their support throughout these many years of education. Whether helping build my fossil collection or not moving to West Virginia so that I could attend Jefferson Sci. & Tech., my parents have encouraged me through it all. The author finally thanks his research advisor Dr. Lauretta for the support for this research, and the freedom to explore the many avenues of study. I wish NASA were a bit more far-sighted so that we could finish up some of our projects. Nonetheless, I greatly appreciate all the help, development, and encouragement! 5 TABLE OF CONTENTS LIST OF FIGURES ...........................................9 LIST OF TABLES ..........................................11 ABSTRACT ...............................................12 CHAPTER 1 INTRODUCTION ................................13 1.1 Phosphorus and Prebiotic Chemistry ...........................17 1.1.1 The RNA World ................................18 1.1.1.1 The “Weak” RNA World ......................19 1.1.1.2 The “Strong” RNA World ......................19 1.1.2 The “Phosphorus Problem” ...........................22 1.2 Why Phosphorus? .....................................24 1.2.1 Characteristics of Phosphorus and Phosphate .................25 1.2.2 Alternatives to Phosphorus .............................32 1.3 Phosphorus in Biology: A Biochemical Survey .................35 1.3.1 Energetic Phosphorus Biomolecules ......................36 1.3.2 Stable Phosphorus Biomolecules ......................39 1.4 Overcoming the “Phosphorus Problem” ......................43 1.4.1 Meteorites as the Source of Phosphorus .................48 CHAPTER 2 PHOSPHORUS FROM METEORITES .................57 2.1 An Experimental Approach to Phosphide Corrosion .................58 2.1.1 Materials and Conditions ...........................59 2.1.2 Experimental Setup ................................65 2.1.3 Analytical Methods ................................67 2.2 Results ..........................................71 2.2.1 Corrosion Experiments ...........................71 2.2.2 Synthetic Experiments ...........................94 2.2.3 Mass Spectral Experiments ...........................95 2.2.4 Electron Paramagnetic Resonance Spectrometry Experiments.....105 2.3 Summary of Solution Chemistry.............................111 2.3.1 Organic Phosphorus Compounds Formed ................114 2.4 Understanding the Corrosion of Schreibersite ................118 2.4.1 Meteoritic Phosphorus Compounds .....................118 2.4.2 Importance of Determining Corrosion Pathway ...........120 CHAPTER 3 SCHREIBERSITE CORROSION IN SITU ................121 3.1 Background .........................................138 6 TABLE OF CONTENTS- Continued 3.2 Visual Characteristics of Corroded Schreibersite Grain ...........124 3.3 Chemical Characteristics of Corroded Schreibersite Grain ...........128 3.3.1 Method ....................................128 3.3.2 Results .........................................128 3.4 Discussion .........................................131 3.4.1 Fe, Ni, P Depletion ...............................138 3.4.2 Ca, K, O and Light Element Addition ................141 3.4.3 Oxidation State of P ...............................146 3.5 Future Work and Conclusions ..........................148 CHAPTER 4 REACTION PATHWAY ..........................150 4.1 Proposed reaction pathway ...............................150 4.1.1 Introduction to Radical Chemistry .....................152 4.1.2 Generation of Radicals ...............................154 4.1.2.1 Stoichiometric Ratios of Phosphorus Compounds ......155 4.1.2.2 Mass Spectral Discussion of Phosphorus speciation ......162 4.1.3 The Inorganic Fe3P Corrosion Reaction Pathway ...........163 4.1.3.1 Predictions of Corrosion Pathway ................166 4.2 Proposed Organic Phosphorus Reaction Pathway ................169 4.2.1 Generation of organic radicals ..........................170 4.2.2 Reaction Pathway ...............................173 4.2.3 Other Organic Compounds ..........................178 4.3 General Implications of Corroding Metal .....................179 4.3.1 The Reaction with Air ...............................180 4.3.2 The Reaction with Acidic Protons .....................181 4.3.2.1 Phosphite Oxidation ..........................182 4.3.2.2 Environmental Chemistry .....................183 4.3.2.3 Phosphide Corrosion: Air vs. Argon ................184 4.3.2.4 Alteration of Meteoritic Organics ................185 4.4 Summary .........................................188 CHAPTER 5 THE FLUX OF METEORITIC P, C AND Ir TO THE EARTH .190 5.1 Types of Extraterrestrial Material ..........................191 5.1.1 Large Impactors ....................................191 5.1.2 Meteorites ....................................192 5.1.2.1 Inorganic Carbon ..........................193 5.1.2.2 Organic Carbon ...............................194 5.1.2.3 Phosphorus ...............................196 5.1.3 IDPs .........................................199 5.1.3.1 Carbon ....................................199 5.1.3.2 Phosphorus ...............................200 5.2 Overview of Late Heavy Bombardment .....................200 7 TABLE OF CONTENTS- Continued 5.3 Methods .........................................203 5.3.1 Large Impactor Flux Calculations .....................205 5.3.2 Meteorite Flux Calculations ..........................207 5.3.3 IDP Flux ....................................213 5.4 Results ..............................................213 5.4.1 Large Impactor Flux and Composition .....................213 5.4.2 Meteorite Flux and Composition .....................217 5.4.3 IDP C & P Fluxes ...............................221 5.4.4 Late Heavy Bombardment ..........................221 5.4.5 Mass Flux of Ir ....................................224 5.5 Discussion .........................................224 5.5.1 Extraterrestrial Fluxes ...............................224 5.5.1.1 Slopes ....................................227