| 
1  Introduction and Motivation .................................. 1
2  Room-Temperature Synthesis and Properties of Metastable
   FeSe ........................................................ 15
   2.1  Introduction ........................................... 15
   2.2  Experimental ........................................... 16
   2.3  Results and Discussion ................................. 20
   2.4  Conclusion ............................................. 31
3  Structural Trends of REFeAsO ................................ 33
   3.1  Introduction ........................................... 33
   3.2  Experimental ........................................... 35
   3.3  Results ................................................ 37
   3.4  Discussion ............................................. 42
   3.5  Conclusion ............................................. 49
4  Tetragonal to Orthorhombic Transition of GdFeAsO ............ 51
   4.1  Introduction ........................................... 51
   4.2  Experimental ........................................... 53
   4.3  Results and Discussion ................................. 53
   4.4  Conclusion ............................................. 61
5  Transport Anisotropy of Large LaFeAsO Single Crystals ....... 63
   5.1  Introduction ........................................... 63
   5.2  Experimental ........................................... 63
   5.3  Results and Discussion ................................. 64
   5.4  Conclusion ............................................. 67
6  Summary and Outlook ......................................... 69
7  Acknowledgement ............................................. 71
8  List of Publications ........................................ 73
Appendices ..................................................... 75
   A  Treatment of Synchrotron Data ............................ 77
   B  Reconstruction of Reciprocal Space ....................... 81
   C  Evaluation of Reflection Splitting ....................... 85
   D  Additional X-Ray Diffraction Data ........................ 89
      D.l  Rietveld Refinement of FeSe ......................... 89
      D.2  Single-Crystal X-ray Diffraction Data of REFeAsO .... 92
      D.3  Synchrotron Data of GdFeAsO at Different
           Temperatures ....................................... 100
References .................................................... 113
 |