The use of supercritical carbon dioxide in solid state chemistry and basic structural investigations with chalcogenide halides of the third main group [Elektronische Ressource] / vorgelegt von Kledi Xhaxhiu
262 pages
English

The use of supercritical carbon dioxide in solid state chemistry and basic structural investigations with chalcogenide halides of the third main group [Elektronische Ressource] / vorgelegt von Kledi Xhaxhiu

-

Le téléchargement nécessite un accès à la bibliothèque YouScribe
Tout savoir sur nos offres
262 pages
English
Le téléchargement nécessite un accès à la bibliothèque YouScribe
Tout savoir sur nos offres

Description

The use of supercritical carbon dioxide in Solid State Chemistry and basic structural investigations with chalcogenide halides of the third main group DISSERTATION Zur Erlangung des Grades eines Doktors Der Naturwissenschaften Vorgelegt von Dipl. -Chem. Kledi Xhaxhiu geb. am 20. 08. 1977 in Durrës eingereicht beim Fachbereich 8 der Universität Siegen Siegen 2005 Berichterstatter: Prof. Dr. H. -J. Deiseroth Prof. Dr. H. Haeuseler Mitglied der Promotionskommission: Prof. Dr. rer. Nat. Xin Jiang Tag der mündlichen Prüfung: 23.11.2005 urn:nbn:de:hbz:467-1964 Acknowledgements This work was completed in the time interval from March 2002 to September 2005 in the Department of Inorganic Chemistry, University of Siegen under the guidance of Prof. Dr. H. J. Deiseroth. I would like to express my grateful thanks to Prof. Dr. H. J. Deiseroth for giving me the freedom on the selection of the working topics, for the exellent supervision and his amicable acquaintance. Special thanks are dedicated to Dr. C. Reiner for the scientifical discussions, criticisms, suggestions and for the SEM and EDX investigations. I would like to thank Dr. M. Schlosser for the Single crystal measurements, Dipl-Chem. Jens Schlirf and staat. gepr.

Informations

Publié par
Publié le 01 janvier 2005
Nombre de lectures 34
Langue English
Poids de l'ouvrage 35 Mo

Extrait

The use of supercritical carbon dioxide in Solid State
Chemistry and basic structural investigations with
chalcogenide halides of the third main group







DISSERTATION
Zur Erlangung des Grades eines Doktors
Der Naturwissenschaften








Vorgelegt von
Dipl. -Chem. Kledi Xhaxhiu
geb. am 20. 08. 1977 in Durrës







eingereicht beim Fachbereich 8
der Universität Siegen
Siegen 2005


























Berichterstatter: Prof. Dr. H. -J. Deiseroth
Prof. Dr. H. Haeuseler
Mitglied der Promotionskommission: Prof. Dr. rer. Nat. Xin Jiang


Tag der mündlichen Prüfung: 23.11.2005

urn:nbn:de:hbz:467-1964
Acknowledgements

This work was completed in the time interval from March 2002 to September 2005 in the
Department of Inorganic Chemistry, University of Siegen under the guidance of Prof. Dr. H. J.
Deiseroth.

I would like to express my grateful thanks to Prof. Dr. H. J. Deiseroth for giving me the freedom on
the selection of the working topics, for the exellent supervision and his amicable acquaintance.

Special thanks are dedicated to Dr. C. Reiner for the scientifical discussions, criticisms, suggestions
and for the SEM and EDX investigations.

I would like to thank Dr. M. Schlosser for the Single crystal measurements, Dipl-Chem. Jens Schlirf
and staat. gepr. Lebensmittelchemikerin Sylvia Wilnewski for the precious advices in the
construction of several devices.

My special thanks are dedicated to Priv. Doc. Dr. L. Kienle for the HRTEM and SAED
measurements.

My sincere acknowledgements are reserved to Prof. Dr. Schneider for his generous help and the
fruitful discussions.

I would like to thank my working colleagues: Michael Wagener, Elmar Neumann, Krasimir
Aleksandrov and all other members of the group of Inorganic Chemistry of the University of
Siegen, whom I had the pleasure to work with.

I would like to thank Dipl. Ing. W. Büdenbender for the assistance and helpful discussions in
several technical problems and Jennifer Hermann for the IR and Raman measurements.

In conclusion, I would like to dedicate my best thanks to my parents Sofika and Skënder as well as
to my brother Jurgen for the continuous encouragement.

Abstract


On the use of supercritical carbon dioxide in Solid State Chemistry and basic structural
investigations with chalcogenide halides of the third main group.

One of the tasks of this work was the exploration of the ability of supercritical CO as a solvent and 2
reaction environment in several reactions involving inorganic compounds of different natures. All
attempts in this field were not successful. The use of scCO as an educt for the permanent fixation 2
of CO (i.e. transformation of oxides or hydroxides in oxide carbonates or carbonates) seems to be a 2
promising field of research.
A second focal point of this work was the preparation, characterisation and the structure
determination of new solids in the ternary systems indium – chalcogen – halogen. The syntheses of
In Ch X (Ch = S, Se; X = Cl, Br) and of derivative compounds were performed using the concept 5 5
of building units. In Ch X represent four new mixed valence compounds crystallising in two 5 5
different structure types, namely the chloride type (In Ch Cl, space group: P2 /m) and the bromide 5 5 1
type (In Ch Br, space group: Pmn2 ). In all these compounds indium occurs in three different 5 5 1
+ 4+ 3+oxidation states as In , covalent (In-In) dumbbells and In suggesting the explicit formula
+ 4+ 3+ 2- -In Ch X = [In ] [(In ) ] 2[In ] 5[Ch ] [X ]. Beside the similarities remarkable differences were 5 5 2
evident not only from the X-ray investigation but mainly from the real structure revealed from
HRTEM investigations. The bromide-type compounds revealed ordered crystals. In contrast to that,
the chloride-type compounds show several anomalies regarding the real structure, e.g. polylamellar
intergrowth of polymorphs, twinning and nanoscale intergrowth of structurally similar compounds
(In S Cl/In S ). 5 5 6 7
A further topic of interest was the high temperature X-ray investigations of powdered samples
K In Se Te , K In Se and In Ch X (Ch = S, Se; X = Cl, Br). The process of lattice expansion 2 12 12 7 2 12 19 5 5
revealed no phase transition for all these compounds within the studied temperature range. The
coefficients of thermal expansion for each compound were determined.


Key words: reactions, scCO , indium chalcogenide halides, crystal structures, real structure, 2
HRTEM, crystal defects, X-ray diffraction, high temperature investigations, expansion coefficient
Kurz-Zusammenfassung

Über die Verwendung des überkritischen Kohlendioxids in der Festkörperchemie und grundlegende
Strukturuntersuchung mit Chalkogenidhalogeniden der dritten Hauptgruppe.

Eines der Ziele dieser Arbeit war die Erforschung der Eigung von überkritischem CO als 2
Lösungsmittel und Reaktionsmedium bei Reaktionen anorganischer Stoffe unterschiedlicher
chemischer Natur. Alle Versuche auf diesem Gebiet waren nicht erfolgreich. Dagegen scheint die
Verwendung des scCO (sc = supercritical) als Edukt für die dauerhafte Fixierung von CO (z.B. 2 2
bei der Umwandlung von Oxyden oder Hydroxyden in Oxyde-Carbonate oder Carbonate) ein
versprechendes Forschungsgebiet zu sein.
Ein zweiter Schwerpunkt der Arbeit war die Präparation, Charakterisierung und
Strukturbestimmung neuer Feststoffe in den ternären Systemen Indium – Chalkogen – Halogen. Die
Synthese von In Ch X (Ch = S, Se; X = Cl, Br) und abgeleiteter Verbindungen erfolgte auf Basis 5 5
eines Baukastenprinzips. In Ch X repräsentieren vier neue gemischtvalente Verbindungen die in 5 5
zwei unterschiedlichen Strukturtypen kristallisieren, nämlich im Chlorid-Typ (In Ch Cl, 5 5
Raumgruppe: P2 /m) und im Bromid-Typ (In ChBr, Raumgruppe: Pmn2). In allen vier 1 5 5 1
+Verbindungen tritt Indium in drei Oxidationstuffen auf; in Form von In , kovalent gebundenen (In-
4+ 3+ + 4+In) Hanteln und als In entsprechend der ionischen Formulierung: In Ch X = [In ] [(In ) ] 5 5 2
3+ 2-2[In ] 5[Ch ] [X-]. Neben diesen Ähnlichkeiten, sind deutliche Unterschiede nicht nur auf basis
der Röntgenbeugungs Untersuchungen offensichtlich sondern hauptsächlich in der Realstruktur die
durch HRTEM Untersuchungen aufgedeckt wurde. Die Bromid-Typ Verbindungen zeigen
geordnete Kristalle. In Gegensatz zum Bromid-Typ zeigen die Chlorid-Typ Verbindungen mehrere
Defekte in der Realstruktur, z.B. polylamellare Verwachsungen von Polymorphen, Verzwillingung
und nanoskaligen Verwachsungen von strukturell verwandten Verbindungen (In Ch Cl/In S ). 5 5 6 7
Ein weiteres interessante Thema waren die Hochtemperatur Röntgenuntersuchungen gepulverter
Proben von K In Se Te , K In Se und In Ch X (Ch = S, Se; X = Cl, Br). Der Verlauf der 2 12 12 7 2 12 19 5 5
Zelleausdehnung zeigte für alle untersuchten Verbindungen innerhalb des untersuchten
Temperaturbereiches keine Phasenübergänge. Für jede der untersuchten Verbindungen wurden die
thermischen Ausdehnungskoeffizienten bestimmt.
Schlüsselwörter: Reaktionen, überkritisches CO, Indium Chalkogenidhalogenide, 2
Kristallstrukturen, Realstruktur, HRTEM, Kristalldefekte, Hochtemperaturuntersuchungen,
Ausdehnungskoeffizient Contents I

Contents

1 Introduction …………………………………………………………...... 1
1.1 Motivation………………………………………………………………………. 3

2 Experimental……………………………………………………………. 5
2.1 Preparation procedure……………………………………………………........... 5
2.2 Characterisation……………………………………………………………........ 7
2.2.1 Infrared spectroscopy measurements (MIR and FIR)……………………. 7
2.2.2 Raman spectroscopy measurements………………………………........... 7
2.2.3 Thermal Analysis………………………………………………………… 8
2.2.4 X-Ray powder investigations…………………………………………….. 8
2.2.5 Scanning Electron Microscopy (SEM) and Electron Beam Microanalysis
(EBMA)………………………………………………………………….. 9
2.2.6 Transmission Electron Microscopy (TEM)……………………………… 9
2.2.7 X-ray single crystal analysis on STOE - IPDS single axis diffraction
System……………………………………………………………………. 10

3 Reactions of some inorganic compounds in supercritical CO ……….2 12
3.1 Introduction……………………………………………………………………... 12
3.2 The definition of the supercritical fluid………………………………………… 13
3.3 The solubility in supercritical region…………………………………………… 19
3.4 Overview of the method………………………………………………………… 22
3.5 Devices for the production of dry ice…………………………………………... 23
3.5.1 The purifying subsystem…………………………………………………. 23
3.5.2 The metering subsystem…………………………………

  • Univers Univers
  • Ebooks Ebooks
  • Livres audio Livres audio
  • Presse Presse
  • Podcasts Podcasts
  • BD BD
  • Documents Documents