Preparation, structure and properties of new ternary chalcogenides and germanides of the metals from the first transition series, Cr, Mn, Fe and Ni [Elektronische Ressource] / vorgelegt von Krasimir Aleksandrov

Aleksandrov, Krasimir

Informations

• Publié par: universitat_siegen
• Publié le: 01 janvier 2005
• Nombre de lectures: 8
• Langue: English
• Poids de l'ouvrage: 8 Mo

Extrait

Preparation, Structure and Properties of New Ternary Chalcogenides
and Germanides of the Metals from the First Transition Series, Cr,
Mn, Fe and Ni






DISSERTATION
zur Erlangung des Grades eines Doktors
der Naturwissenschaften





vorgelegt von
Dipl. Ing. – Chem. Krasimir Aleksandrov
geb. am 03.12.1975 in Vratsa





eingereicht beim Fachbereich 8
der Universität Siegen
Siegen 2005

























Berichterstatter: Prof. Dr. H. -J. Deiseroth
Prof. Dr. H. Haeuseler

Tag der mündlichen Prüfung: 30.06.2005


urn:nbn:de:hbz:467-1058 Acknowledgements

This work was completed during the time from June 2001 to May 2005 in the Inorganic
Chemistry Department, University of Siegen under the guidance of Prof. Dr. H. J. Deiseroth.

I would like to express my heartfelt gratitude to my supervisor Prof. Dr. H. J. Deiseroth for
his elaborate guidance and unlimited enthusiasm.

I would like to thank Dr. C. Reiner for our many fruitful discussions and SEM investigations
and Dr. M. Schlosser for the single crystal measurements.

I am also very gratefully to both Dipl. Chem. J. Schlirf and Dr. M. Aleksandrova for their
assistance in carrying out the DTA and IR measurements.

I would like to thank my colleagues Dipl. Chem. Michael Wagener, Dipl. Chem. Kledi
Xhaxhiu and all the other members of the Inorganic Chemistry group of the University of
Siegen, with whom I had the pleasure of working.

I am especially pleased to acknowledge the assistance of Dipl. Ing. W. Büdenbender in the
technical problems.

I would like to thank Dr. R. K. Kremer from the Max – Planck – Institute for Solid State
Research, Stuttgart for carrying out the magnetic measurements.

Finally, I would especially like to thank my wife Margarita and our son Ivan as well as my
parents Hristina and Ivan, and my brother Rosen, who were a constant source of
encouragement and support. Contents 1
Contents

1 Introduction .................................................................................................................... 4

2 Motivation........................................................................................................................ 5

3 Experimental................................................................................................................... 7
3.1 Preparation procedure.................................................................................................7
3.2 Vacuum technique.......................................................................................................8
3.2.1 Vacuum system outline ................................................................................... 8
3.2.2 Evacuation procedure....................................................................................10
3.3 X – ray characterization methods.............................................................................. 11
3.3.1 Introduction...................................................................................................11
3.3.2 Powder X – ray methods ............................................................................... 13
3.3.3 Single crystal X – ray structure analyse ........................................................ 14
3.4 Thermal analysis.......................................................................................................14
3.5 Scanning electron microscopy .................................................................................. 14
3.6 Infrared spectroscopy................................................................................................15
3.7 Magnetic measurements............................................................................................16

4 The compound Mn GeSe ........................................................................................ 17 2 4
4.1 Introduction............................................................................................................... 17
4.2 Preparation and properties.........................................................................................18
4.3 Characterization........................................................................................................21
4.4 Single crystal analysis ............................................................................................... 26
4.5 Structure description and discussion......................................................................... 27
4.6 MAPLE calculations.................................................................................................32
4.7 Olivine or spinel structure ......................................................................................... 34
4.8 Magnetic measurements............................................................................................35


Contents 2
5 Cr Ge Se – a new member of M X Y compounds 2 2 6 2 2 6
mn(M = Transition metal, X = Si, Ge, Y = Chalcogen) ....................................... 37
5.1 Structure – chemical relations................................................................................... 37
5.2 Preparation and properties.........................................................................................43
5.3 Characterization........................................................................................................46
5.4 Outlook...................................................................................................................... 50

6 M GeTe compounds (M = Fe, Ni) ........................................................................ 51 3 2
6.1 Introduction............................................................................................................... 51
6.2 The compound Fe GeTe .......................................................................................... 52 3 2
6.2.1 Preparation and properties.............................................................................52
6.2.2 Characterization............................................................................................55
6.2.3 Single crystal analysis ................................................................................... 57
6.2.4 Structure description and discussion............................................................. 58
6.2.5 Magnetic measurements................................................................................65
6.3 The compound Ni GeTe 67 3 2
6.3.1 Preparation and properties.............................................................................67
6.3.2 Characterization............................................................................................70
6.3.3 Single crystal analysis 75
6.3.4 Structure description and discussion............................................................. 76
6.3.5 Magnetic measurements................................................................................82

7 Synthesis and characterisation of nanoscale hydroxylapatite .................... 83
7.1 Introduction............................................................................................................... 83
7.2 Experimental outline.................................................................................................84
7.3 Results and discussion...............................................................................................85
7.3.1 IR characterization........................................................................................85
7.3.2 X – ray characterization ................................................................................ 91
7.3.3 SEM investigation.........................................................................................93
7.3.4 Influence of the temperature ......................................................................... 97
7.3.5 Conclusion...................................................................................................100 Contents 3
8 Preliminary experiments to synthesise new ternary transition
metal chalcogenides .................................................................................................. 102
8.1 Research on transition metal olivines, A BX 2 4
Lkdfgj (A = transition metal, B = Si, Ge, Sn, X = Se, Te).................................................. 102
8.2 Attempts to prepare ternary compounds of the type M X Y 2 2 6
Lssdlf (M = transition metal, X = Si, Ge, Sn, Y = S, Se, Te) ............................................ 105
8.3 Research on M BX compounds 3 2
Kljf (M = transition metal, B = Si, Ge, Sn, X = Se, Te) ................................................. 108

9 Summary ...................................................................................................................... 110

10 References .................................................................................................................... 113

11 Appendix 131
11.1 Data for Mn GeSe .....