Spin-crossover in metallomesogens of iron(II) [Elektronische Ressource] / Maksym Seredyuk

Maksym Seredyuk

Informations

• Publié par: johannes_gutenberg-universitat_mainz
• Publié le: 01 janvier 2008
• Nombre de lectures: 26
• Poids de l'ouvrage: 13 Mo

Extrait

Spin-crossover in metallomesogens of iron(II)



Dissertation
zur Erlangung des Grades
“Doktor der Naturwissenschaften”

am Fachbereich Chemie, Pharmazie und Geowissenschaften
der Johannes Gutenberg-Universität
in Mainz


Maksym Seredyuk
geboren in Smela, Ukraine

Mainz 2008Ich erkläre hiermit an Eides statt, dass ich diese Arbeit selbständig und ohne unerlaubte
Hilfsmittel angefertigt habe.

Mainz, April 2008



































1. Berichterstatter:
2. Berichterstatter:
3. Berichterstatter:

Tag der mündlichen Prüfung: 26. Mai 2008







I am at a loss to give a distinct idea of the nature of
this liquid, and cannot do so without many words.

Edgar Allan Poe
“The Narrative of Arthur Gordon Pym of Nantucket”
(1837)



Я вагаюся дати чітке визначення природи цієї
рідини, тому мені не уник нути багатьох слів.

Едґар Алан По
«Оповідь Арт у ра Гордона Піма з Нантакета»
(1837) 1
Table of Contents
List of Abbreviations................................................................................................................6
1 Introduction ........................................................................................................................8
1.1 Introduction............................................................................................................8
1.2 Motivation and objectives....................................................................................11
1.3 Spin-crossover phenomenon and LIESST effect ...............................................13
1.3.1 Background of spin-crossover phenomenon ..............................................13
1.3.2 Nomenclature..............................................................................................18
1.3.3 Physical response........................................................................................18
1.3.4 Influence on spin-crossover behavior.........................................................20
1.3.5 Slichter-Drickamer Model..........................................................................22
1.3.6 LIESST effect.............................................................................................24
1.4 Liquid crystallinity phenomenon ........................................................................26
1.4.1 Organic liquid crystals................................................................................26
1.4.2 Metallomesogens31
1.4.3 Melting point of alkyl derivatives ..............................................................33
2 Mononuclear iron(II) systems .........................................................................................34
2.1 Parent systems......................................................................................................34
2.1.1 Introductory remarks..................................................................................34
2.1.2 Overview of the literature on iron(II)- and iron(III)-based polypodand
complexes ...................................................................................................34
2.1.3 Synthesis.....................................................................................................38
2.2 Structural and physical characterization of compounds 1 and 1-Zn .............41
2.2.1 Introductory remarks41
2.2.2 Variable-temperature X-ray single crystal diffraction of 1 and 1-Zn ........42
2.2.3 UV/VIS spectroscopy.................................................................................55
2.2.4 Magnetic properties of 1.............................................................................56
2.2.5 Mössbauer spectroscopy study of 1............................................................56
2.2.6 Discussion...................................................................................................59
2.2.7 Summary.....................................................................................................60
2.3 Characterization and physical properties of compounds 2–6 ..........................62
2.3.1 Introductory remarks..................................................................................62
2 Table of contents

2.3.2 Crystal structures of 2–6 ............................................................................ 62
2.3.3 IR spectroscopy and mass spectroscopy .................................................... 70
2.3.4 UV/VIS spectroscopy of 2–6 ..................................................................... 72
2.3.5 Magnetic properties and Mössbauer spectroscopy .................................... 73
2.3.6 Discussion.................................................................................................. 78
2.3.7 Summary.................................................................................................... 83
2.4 Mononuclear metallomesogenic systems of iron(II) ......................................... 85
2.4.1 Introductory remarks.................................................................................. 85
2.4.2 Overview of the literature on iron(II)-based mononuclear
metallomesogens with spin-crossover properties ...................................... 85
2.4.3 Synthesis 87
2.4.4 Nomenclature............................................................................................. 88
2.4.5 The role of the constituents in compounds C -7–C -29............................ 90 n n
2.4.6 The packing of compounds C -7–C -29.................................................... 90 n n
2.5 Characterization and physical properties of compounds C -7–C -18 ........... 92 n n
2.5.1 Introductory remarks.................................................................................. 92
2.5.2 Crystal structure of C -7 ............................................................................ 92 6
2.5.3 C -8........................................................................... 94 12
2.5.4 Mass spectroscopic, TGA and IR data....................................................... 97
12.5.5 UV/VIS and H NMR spectroscopy .......................................................... 99
2.5.6 Magnetic properties.................................................................................. 101
2.5.7 XRD data.................................................................................................. 105
2.5.8 DSC and POM data.................................................................................. 112
2.5.9 Mössbauer spectroscopy.......................................................................... 116
2.5.10 Discussion................................................................................................ 122
2.5.11 Summary .................................................................................................. 125
2.6 Characterization and physical properties of compounds C -19–C -23 ....... 126 n n
2.6.1 Introductory remarks................................................................................ 126
2.6.2 Crystal structure of C -19 ........................................................................ 126 6
2.6.3 Mass spectroscopic, TGA and IR data..................................................... 132
2.6.4 UV/VIS spectroscopy.............................................................................. 133
2.6.5 Magnetic properties.................................................................................. 134
2.6.6 XRD measurements................................................................................. 137
2.6.7 DSC and POM data.................................................................................. 139
2.6.8 Mössbauer spectroscopy.......................................................................... 141 Table of contents 3
2.6.9 Discussion.................................................................................................146
2.6.10 Summary...................................................................................................149
2.7 Characterization and physical properties
of compounds C -24 and C -25......................................................................151 18 18
2.7.1 Introductory remarks................................................................................151
2.7.2 Mass spectroscopic, TGA and IR data .....................................................151
2.7.3 UV/VIS spectroscopy...............................................................................152
2.7.4 Magnetic properties and Mössbauer spectroscopy...................................153
2.7.5 XRD, DSC and POM data........................................................................154
2.7.6 Discussion.................................................................................................156
2.7.7 Summary...................................................................................................157
2.8 Characterization and physical pro