On the way to molecular optical switches [Elektronische Ressource] : a solid-state NMR study of trans-cinnamic acids / Isa Alexandra Queiroz da Fonseca

Michael Müller

Informations

• Publié par: rheinisch-westfalischen_technischen_hochschule_-rwth-_aachen
• Publié le: 01 janvier 2008
• Nombre de lectures: 14
• Langue: English
• Poids de l'ouvrage: 4 Mo

Extrait

On the way to molecular optical switches:
A solid-state NMR study of trans-cinnamic acids
Von der Fakultät für Mathematik, Informatik und Naturwissenschaften der RWTH Aachen
University zur Erlangung des akademischen Grades einer Doktorin der
Naturwissenschaften gehnemigte Dissertation
vorgelegt von
Dipl. Ing.
Isa Alexandra Queiroz da Fonseca
aus Lisboa, Portugal
Berichter: Universitätsprofessor Dr. Dr. h.c. Bernhard Blümich
Hochschuldozent PD Dr. Marko Bertmer
Tag der mündlichen Prüfung: 13. Juni 2008
Diese Dissertation ist auf den Internetseiten der Hochschulbibliothek online verfügbar.WICHTIG: D 82 überprüfen !!!
Berichte aus der Chemie
Isa Alexandra Queiroz da Fonseca
On the way to molecular optical switches:
A solid-state NMR study of trans-cinnamic acids
trans kursiv
D 82 (Diss. RWTH Aachen)
Shaker Verlag
Aachen 2008Bibliographic information published by the Deutsche Nationalbibliothek
The Deutsche Nationalbibliothek lists this publication in the Deutsche
Nationalbibliografie; detailed bibliographic data are available in the Internet at
http://dnb.d-nb.de.
Zugl.: Aachen, Techn. Hochsch., Diss., 2008
Copyright Shaker Verlag 2008
All rights reserved. No part of this publication may be reproduced, stored in a
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Printed in Germany.
ISBN 978-3-8322-7614-0
ISSN 0945-070X
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imagination embraces the whole world.
Albert EinsteinContents
Contents
Symbols and abbreviations................................................................................................. 7
1. Introduction ..................................................................................................................... 9
2. Theoretical background................................................................................................ 15
2.1 Anisotropic nuclear spin interactions.................................................................... 15
2.2 Experimental Techniques ....................................................................................... 20
2.2.1 Magic angle spinning ......................................................................................... 20
2.2.2 Cross polarization under magic angle spinning.................................................. 21
2.2.3 Multidimensional NMR spectroscopy................................................................ 22
2.2.4 2D PASS............................................................................................................. 23
2.2.5 2D BABA ........................................................................................................... 25
2.3 Chemical shift calculations ..................................................................................... 27
2.4 Kinetics of phase changes 27
3. Unsubstituted trans-cinnamic acid polymorphs: αααα- and ββββ-cinnamic acid and their
photoreaction products ..................................................................................................... 31
3.1 Experimental Section .............................................................................................. 32
133.2 C CPMAS spectroscopy ....................................................................................... 35
3.2.1 Identification of polymorphs .............................................................................. 35
3.2.2 Photoreaction products 39
3.2.2 Kinetics of photoreaction.................................................................................... 41
3.2.3 Chemical shift anisotropy................................................................................... 43
13.3 H high-speed MAS ................................................................................................. 48
13.3.1 H chemical shift and intermolecular distances.................................................. 49
1 13.3.2 H- H correlation experiments............................................................................ 52
3.4 Conclusions .............................................................................................................. 60
4. α-trans cinnamic acid derivatives: o-methoxy and o-ethoxy cinnamic acid and their
photoreaction products ..................................................................................................... 63
4.1 Experimental Section .............................................................................................. 63
134.2 C CPMAS spectroscopy ....................................................................................... 65
4.2.1 Characterization of the derivatives..................................................................... 65
4.2.2 Kinetics of photoreaction.................................................................................... 69
4.2.3 Chemical shift anisotropy................................................................................... 74
14.3 H High-speed MAS ................................................................................................ 79
14.3.1 H chemical shift and intermolecular distances.................................................. 79
1 14.3.2 H- H correlation experiments............................................................................ 81
4.4 Conclusions .............................................................................................................. 88
5. β-trans-cinnamic acid derivatives: o-, m, p-bromo cinnamic acid and their
photoreaction products ..................................................................................................... 91
5.1 Experimental Section .............................................................................................. 92
135.2 C Spectra ............................................................................................................... 93
5.2.1 Characterization of the derivatives..................................................................... 93
5Contents
5.2.2 Kinetics of photoreaction ................................................................................. 100
5.2.3 Chemical shift anisotropy................................................................................. 106
15.3 H High-speed MAS .............................................................................................. 113
15.3.1 H chemical shift and intermolecular distances ............................................... 113
1 15.3.2 H- H correlation experiments ......................................................................... 115
5.4 Conclusions ............................................................................................................ 120
6. Summary and outlook................................................................................................. 123
Appendix .......................................................................................................................... 127
A.1 Chemical shift anisotropy tensor tables ............................................................. 127
A.2 SIMPSON simulation programs 137
A.2.1 Simulation of the F1-projections of the 2D-BABA experiment ..................... 137
A.2.2 Simulation of the spinning side band pattern of the non-rotor synchronized 2D-
BABA experiment..................................................................................................... 141
References ........................................................................................................................ 145
6Symbols and abbreviations
Symbols and abbreviations
AFM atomic force microsospy
B static magnetic field vector 0
B radio frequency field 1
CPMAS cross polarization under magic angle spinning
CSA chemical shift anisotropy
d dipolar coupling constante
D dipolar couplitensor
DD heteronuclear dipolar decoupling
DQ double quantum
GB gigabytes
GIAO gauge-including atomic orbitals
H Hamilton operator
Planck’s constant divided by 2
I spin operator
I I spin operator of spin I
S
I spin operator of spin S
JMAK Johnson-Mehl-Avrami-Kolmogorov
k rate constante
n Avrami exponent
NMR nuclear magnetic resonance
P coupling tensor
r internuclear distance
rf radio frequency
r hydrogen-hydrogen distance HH
SGU signal generating unit
SQ single quantum
T longitudinal relaxation time 1
TB terabytes
7Symbols and abbreviations
TMS tetramethylsilane
UV ultraviolet
UV-VISltraviolet-visible
V volume
Δ anisotropyparameter
Δ reduced anisotropy red
δ , δ , δ principle values of the chemical shift tensor 11 22 33
δ isotropic chemical shift iso
γ gyromagnetic ratio
γ gyromagnetic ratio of spin i i
γ gyromagnetic ratio of spin j j
η asymmetry parameter
μ magnetic permeabilityon vacuum 0
ν frequency
ν frequency of the reference ref
θ angle between sample rotation axis and applied field r
σσσσ chemical