Dissertation zur Erlangung des Doktorgrades der Fakultät für Chemie und Pharmazie der Ludwig-Maximilians-Universität München Novel Contributions to the Solid-State Chemistry of Diazenides Sebastian Bernhard Schneider aus München, Deutschland 2013 Erklärung Diese Dissertation wurde im Sinne von § 7 der Promotionsordnung vom 28. November 2011 von Herrn Prof. Dr. Wolfgang Schnick betreut. Eidesstattliche Versicherung Diese Dissertation wurde eigenständig und ohne unerlaubte Hilfe erarbeitet. München, 11.11.2013 …………………………………… (Sebastian Bernhard Schneider) Dissertation eingereicht am 11.11.2013 1. Gutachter: Prof. Dr. Wolfgang Schnick 2. Gutachter: Prof. Dr. Dirk Johrendt Mündliche Prüfung am 16.12.2013 To my family ACKNOWLEDGEMENTS First, I would like to express my gratitude to my supervisor Prof. Dr. Wolfgang Schnick for the opportunity to do my PhD under his guidance. Throughout the entire work, I appreciated his extraordinary expertise, the given freedom in research and writing and the support at any time. For being the co-referee of my thesis, I thank Prof. Dr. Dirk Johrendt. I am thankful to Prof. Dr. Konstantin Karaghiosoff, PD Dr. Markus Lackinger, Prof. Dr. Hans-Christian Böttcher, and Prof. Dr. Jörn Schmedt a. d. Günne for being available as examiners in my viva-voce. In addition, I have to thank various co-workers spread all over Germany and Europe. Hereby, special thanks go to • Volker L. Deringer, Dr. Ralf P. Stoffel as well as Prof. Dr. Richard Dronskowski (RWTH Aachen, Germany) for their long-lasting support with numerous theoretical calculations concerning novel diazenide compounds and for their ongoing enthusiasm until we found the final ground state. • Dr. Lkhamsuren Bayarjargal, Dr. Alexandra Friedrich and Prof. Dr. Björn Winkler (all Goethe-University Frankfurt, Germany) for their support and high-level expertise in the preparation of diamond-anvil cells. • Dr. Zuzana Konôpková, Dr. Hanns-Peter Liermann and Dr. Wolfgang Morgenroth (all Deutsches Elektronen Synchrotron DESY, Hamburg, Germany) as well as Dr. Sylvain Petitgirard and Dr. Ashkan Salamat (both European Synchrotron Radiation Facility ESRF, Grenoble, France) for their outstanding support and awesome working atmospheres during all the beam times whenever I visited the synchrotrons. • Dr. Marcus R. Schwarz (High-Pressure Research Center Freiberg, Germany) for the hardness measurements he conducted for one of my samples. • Prof. Dr. Gunnar Jeschke and Henryk Laqua (both ETH Zurich, Switzerland) for the various ESR experiments as well as helpful discussions. • Dr. Rainer Frankovsky and Gina M. Friederichs (both LMU) for their patience in conductivity and magnetic measurements. Additionally I have to thank you Rainer for the numerous DFT calculations on band structures and bonding situations. • Martin “Saubatzi” Mangstl (University of Siegen) for the persistent NMR measurements and nights at the spectrometer – whereby I wonder whether “to thank” is the right choice. Just kidding, it was fun! • Viola Duppel (Max-Planck-Institute Stuttgart, Germany) for the TEM measurements and the phenomenal report on as-obtained data. • Markus Seibald for his outstanding experience and support in the analysis of electron diffraction data. For analytical measurements and help with the hardware I would like to thank the following persons (in alphabetical order): Thomas Miller, Christian Minke, Marion Sokoll and Wolfgang Wünschheim (all LMU). I also have to thank our secretary Olga Lorenz for her helpfulness and support in all administrative concerns. I am indebted to my bachelor and research students Tanja Holzmann, Philipp Ratza and Juliane Stahl for their excellent work and pleasant atmosphere. Special thanks to my ex- and current lab-mates in D2.110, Florian Pucher, Dominik Baumann, Alexey “Russetsky” Marchuk, Frank Tambornino as well as Cora Hecht and Dr. Stefan Sedlmaier. Especially to Flo, Dodo, Russestky and Sedl for their support during the entire work, for various constructive discussions and a lot of gorgeous lab times. Further, I would like to thank all my colleagues in the working groups Schnick, Johrendt, Lotsch, Oeckler, Schmedt a. d. Günne and Hoch I did not explicitly mention. I really appreciated the nice and friendly working atmosphere and the awesome events such as for example the phenomenal Sing star evenings. Stephan Werner, Christian Ziegler and Stephan Hug…what shall I say? You guys are great! I will never forget – however unfortunately some of them I already did – our numerous, awesome, funny, excessive, outstanding, extraordinary, unexpected (I could continue like this for hours) times, lab-hours/days, events, parties and so on and on (again I could continue listing)! In addition, besides private conversations you always had an open ear for chemical discussions and problems and made my entire PhD time unforgettable. I wish you all the best for the future and I do hope we stay in contact! Tanja, special thanks to you for your support, patience – especially patience – and encouragement during this thesis. You are the best! Particularly I want to thank my parents and my sister Hanna, who made my entire academic life and studies possible. Without you, I would not stand here! Thanks for everything you did! So eine Arbeit wird eigentlich nie fertig, man muss sie für fertig erklären, wenn man nach der Zeit und den Umständen das Möglichste getan hat. (Johann Wolfgang von Goethe) Ich habe fertig! (Giovanni Trapattoni) I Table of Contents TABLE OF CONTENTS 1. INTRODUCTION ............................................................................................................ 1 1.1 INDUSTRIAL NITROGEN FIXATION ................................................................................ 1 1.2 BIOLOGICAL NITROGEN FIXATION ............................................................................... 2 1.3 SYNTHETIC NITROGEN FIXATION ................................................................................. 4 1.4 NITROGEN FIXATION IN SOLID-SATE CHEMISTRY....................................................... 8 2. BINARY ALKALINE EARTH DIAZENIDES ........................................................... 27 2.1. SYNTHESIS OF ALKALINE EARTH DIAZENIDES MAEN2 (MAE = CA, SR, BA) BY CONTROLLED THERMAL DECOMPOSITION OF AZIDES UNDER HIGH PRESSURE ...... 28 2.1.1 Introduction .......................................................................................................... 29 2.1.2 Experimental Section ............................................................................................ 30 2.1.3 Results and Discussion ......................................................................................... 34 2.1.4 Conclusions .......................................................................................................... 41 2.1.5 Bibliography ......................................................................................................... 41 2.2 FURTHER ALKALINE EARTH DIAZENIDES .................................................................. 45 2.2.1 Experimental Section ............................................................................................ 45 2.2.2 Results, Discussion and Conclusion ..................................................................... 46 2.2.3 Bibliography ......................................................................................................... 47 3. BINARY ALKALI DIAZENIDES ............................................................................... 49 3.1. HIGH-PRESSURE SYNTHESIS AND CHARACTERIZATION OF THE ALKALI DIAZENIDE LI2N2 ............................................................................................................................. 50 3.1.1 Introduction with Results and Discussion ............................................................ 51 3.1.2 Bibliography ......................................................................................................... 54 3.2 FURTHER ALKALI DIAZENIDES ................................................................................... 58 3.2.1 Experimental Section ............................................................................................ 58 3.2.2 Results, Discussion and Conclusion ..................................................................... 60 3.2.3 Bibliography ......................................................................................................... 63 4. MATERIALS PROPERTIES OF BINARY DIAZENIDES ...................................... 66 Table of Contents II 4.1. ELECTRONIC AND IONIC CONDUCTIVITY IN ALKALINE EARTH DIAZENIDES MAEN2 (MAE = CA, SR, BA) AND IN LI2N2 ............................................................................... 67 4.1.1 Introduction .......................................................................................................... 68 4.1.2 Experimental Section ............................................................................................ 69 4.1.3 Results and Discussion ......................................................................................... 72 4.1.4 Conclusion ............................................................................................................ 79 4.1.5 Bibliography ......................................................................................................... 80 4.2 HIGH-PRESSURE BEHAVIOR OF BINARY DIAZENIDES ................................................ 86 4.2.1 Introduction .........................................................................................................