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Information to Users INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand corner and continuing from left to right in equal sections with small overlaps. Each original is also photographed in one exposure and is included in reduced form at the back of the book. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality9 "6" black x and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. University Microfilms International A Bell & Howell Information Company 300 North Zeeb Road. Ann Arbor, Ml 48106-1346 USA 313/761-4700 800/521-0600 Order Number 9401351 Preparation of ytterbium and europium borides from Yb(II) and Eu(II) boron hydride precursors Salupo, Terese Ann, Ph.D. The Ohio State University, 1993 UMI 300 N. ZeebRd. Ann Arbor, MI 48106 Preparation of Ytterbium and Europium Borides from Yb(ll) and Eu(ll) Boron Hydride Precursors Dissertation Presented in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in the Graduate School of The Ohio State University by Terese A. Salupo, B.S. ********** The Ohio State University 1993 Dissertation Committee: Approved by: Dr. Bruce E. Bursten Dr. James A. Cowan Dr. Sheldon G. Shore Advisor Department of Chemistry To Mom and Dad ACKNOWLEDGEMENTS I would like to thank Professor Sheldon G. Shore for his guidance and support during my years in the Shore Group. I especially appreciate his sense of humor which made for many moments of laughter. I thank my mentor, Professor Howard C. Knachel, for his neverending enthusiasm for chemistry and encouragement throughout both my undergraduate and graduate studies. I thank Ms. Marilyn Frohwerk for a challenging and enjoyable first exposure to chemistry which greatly influenced me to pursue a career in the field. A special thank you goes to the Shore Group members past and present for being my family away from home. Never a day has gone by that I did not hear laughter on the second floor of Evans Lab. Although the names are too numerous to mention, I would especially like to acknowledge Drs. Tim Coffy, Deborah McCarthy, Tim Shay, Jim White, and Jung Oh and also Bob Godfroid and Janghoon Chung. Words cannot express my gratitude to Debbi McCarthy, Tim Shay and Jung Oh for making me laugh during the toughest year of my life. Thanks to Fr. Vinny McKiernan and my movie companions, Anne Petratis and Dr. Nick Pontikos, for reminding me that there is more to life than just chemistry. I thank David Chang and Dick Weisenberg for their assistance with gas mass spectrometry and Clare McDonald and John Mitchell for their assistance with Scanning Electron Microscopy. The most important thank you goes to Mom and Dad and Grandma and Grandpa Kulchar. This degree is just as much yours as it is mine because of the lifetime I have had of your love and sacrifice which have shaped me into what I am today. You are the best teachers I have ever had. Thank you also to the rest of the Salupo clan, Judy, Pat, Nick, Patti, Anthony, Vince, Stacy, and Nicholas, for always being my stability when things get rough. I love you more than words can say. Last and certainly not least, I thank the Big Guy for His many, many blessings and for the strength and wisdom to get through all the graduate school obstacles. VITA September 11, 1964 Born: Garfield Heights, Ohio 1986 B.S. Chemistry, University of Dayton, Dayton, Ohio. 1989-1991 Graduate Research Assistant Department of Chemistry The Ohio State University Columbus, Ohio. 1987-1989 Graduate Teaching Assistant 1991 -1993 Department of Chemistry, The Ohio State University Columbus, Ohio. PUBLICATIONS "Clusters Derived from [OSgCO^ ]2'. Crystal Structures of [Et4N] [HOs3(CO) 11 ] and H2Os4(CO)13h, J.A. Krause, U. Siriwardane, T.A. Salupo, J.R. Wermer, D. Knoeppel, and S.G. Shore, J.Organometallic Chemistry, in press. "Synthesis of Dinuclear Carbonylates of the Iron Subgroup: [M2(CO)8]2' (M *= Ru, Os) and [FeRu(CO)g]2". Structures of [PPh4]2[FeRu(CO)8] CH3CN and [PPh4]2[Fe2(CO)8]'2CH3CN", N.K. Bhattacharyya, T.J. Coffy, W. Quintana, T.A. Salupo, J.C. Bricker, T.B. Shay, M. Payne, and S.G. Shore, Organometallics 9 (1990) 2368-2374. "Symmetrical Ring Cleavage of the Gold (I) Phosphorus Ylide Dimer [Au(CH2)2PPh2]2 by Hydrogen Halides in Toluene", H.C. Knachel, H.J. Galaska, T.A. Salupo, J.P. Fackler, Jr., and H.H. Murray, Inorganica Chimica Acta, 126 (1987) 7-10. v "Reactions of HCI(g), DCI(g), and HBr(g) with the Adduct Pyrazine-Phosphorus (V) Chloride", H.C. Knachel, S.D. Owens, S.H. Lawrence, M.E. Dolan, M.C. Kerby, T.A. Salupo, Inorg. Chem. 25 (1986) 4606-4608. FIELDS OF STUDY Major Field: Chemistry Minor Field: Inorganic Chemistry Studies in Bioinorganic and Coordination Chemistry: Professors Daryle H. Busch and Daniel L. Leussing. Studies in Organometallics, Cluster Chemistry, Group Theory and Catalysis: Professors Bruce E. Bursten, Devon W. Meek, Eugene P. Schram, Sheldon G. Shore, and Andrew Wojcicki. Studies in Ceramic Engineering: Professors Charles H. Drummond III and Sheikh A. Akbar. TABLE OF CONTENTS D E D IC A TIO N ........................................................................................................... ii ACKNOWLEDGEMENTS...................................................................................... iii VITA............................................................................................................................ v UST OF TABLES .................................................................................................. ix UST OF FIGURES .................................................................................................. x UST OF ABBREVIATIONS .................................................................................. xiii CHAPTER I. IN TR O D U C TIO N ............................................................................................. 1 II. STATEMENT OF THE PROBLEM ................................................................. 24 III. RESULTS AND DISCUSSION ........................................................................ 27 A. Metathesis Reactions with L^YbClg......................... 28 1. Reaction with KB3H8 .............................................................. 29 2. Reaction with NaBHgCN ....................................................... 34 B. Liquid Ammonia Reduction Reactions ............................................ 41 1. Reactions with NH4B3H8 ....................................................... 42 2. Reactions with [HNMe3]2B12H12 ......................................... 48 3. Reactions with [H N E tg J g B ^ H ^ ............................................ 57 4. Reactions with NH3BH3 ......................................................... 66 5. Reaction with [HNMe3]BgH1 4................................................ 72 6. Reaction with B 10H 1 4 .............................................................. 78 C. Thermal Decomposition Studies of Precursor Complexes 79 1. Pyrolysis of (C H g C N ^ Y b fB H ^ ....................................... 79 2. Pyrolysis of (NH 3 )xYbB12H1 2 ........................................... 81 3. Pyrolysis of (NH3)xEu(B3H8)2 ........................................... 82 vii D. Thin Film Studies ............................................................................... 86 1. YbB2 thin film studies ........................................................... 86 2. Eu B6 thin film studies ........................................................... 91 IV. EXPERIMENTAL............................................................................................. 98 A. A pparatus ............................................................................................. 98 B. Solvents and Reagents........................................................................ 108 C. Preparation of Starting Materials ........................................................ 114 D. R eactions ................................................................................................117 1. Preparation of YbB12H1 2 ......................................................... 117 2. Preparation of EuB12H-|2 ......................................................... 118 3. Preparation of YbB10H1 0 ......................................................... 119 4. Preparation of EuB10H1 0 ......................................................... 120 5. Preparation of (CH3CN)xYb(BH3CN)2 .................................... 121 6. Preparation of (C5H5N)xYb(BH3CN)2 .................................... 122 7. Preparation of (NH3)xYb(NH2BH3)2 .......................................123 8. Preparation of
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