Vibrational spectroscopy and density functional theory calculations on biological molecules [Elektronische Ressource] / vorgelegt von Niculina Peica

Sujets

• Biologie

Informations

• Publié par: julius-maximilians-universitat_wurzburg
• Publié le: 01 janvier 2006
• Nombre de lectures: 31
• Langue: English
• Poids de l'ouvrage: 13 Mo

Extrait

Vibrational sp ectroscopy and
density functional theory cal culations
on biological molecule s
Disse rtation
zur Er langung des
Naturwissenscha ftlichen Doktorg rades
der Ba yerischen Julius-Maxi milians- Universität Wü rzburg
vorgelegt von
Niculina Peic a
aus
Potcoava, Rum änien
Würzburg 2006II
Eingerich tet am: …………………………………………………………….
bei der Fakultät für Chem ie und P harmazie
1. Gutachter: …………………………………………………………………….
2. Gutachter: …………………………………………………………………….
der Di ssertation
1. Prüfer …………………………………………………………………….
2. Prüfer …………………………………………………………………….
3. Prüfer …………………………………………………………………….
des Öffentlichen Promotionskolloquiums
Tag der mündl ichen Prüfung: …………………………………………….
Doktorurkunde au sgehändigt am: ……..…………………………………... III
in memory of my father
to my familyIV Table o f Conten ts V
Table of Contents
Table of Contents ............................................................................................................................V
Abbreviations and S ymbols......................................................................................................IX
Chapter I
Introduction ......................................................................................................................................1
Chapter II
Theoretical background ...................................................................................................................5
II.1 Ultra- violet and visible spectroscop y...................................................................................6
II.1 .1 Basic c oncepts of electronic spectroscopy..........................................................................6
II.1 .2 Chrom ophores and transitions...........................................................................................8
II.1 .3 F luorescence....................................................................................................................9
II.1 .4 Solvent effects...............................................................................................................10
II.1 .5 H ydrogen bonding..........................................................................................................11
II.2 Vibrational spectroscopy....................................................................................................13
II.2.1 Scattering of light...........................................................................................................13
II.2.2 Infrared and Ram an spe ctroscopy....................................................................................14
II.2.3 Fou rier-tr ansform Ram an spectroscopy...........................................................................22
II.2.4 Reson ance Ram an sp ectroscopy......................................................................................23
II.2.5 Surface enhanced Ram an spectroscopy............................................................................25
II.2.5 .1 E lectromagnetic enhancement mechanism................................................................27
II.2.5 .2 Charge transfer enhancement mechani sm30
II.2.5 .3 Su rface enhanced resonance Raman sca ttering.........................................................32
II.2.5 .4 Su rface enhanced Raman scattering subs trates33
II.3 Densit y functional theor y...................................................................................................36
II.3 .1 The Kohn-Sha m approach..............................................................................................36
II.3 .2 Exch ange and correlation energy functionals....................................................................38
II.3 .3 Basis s et effects.............................................................................................................40
II.3.3 .1 S later and Gaussian t ype orbitals40
II.3.3 .2 Pop le s tyle bas is s ets...............................................................................................42
II.3.3 .3 Hay-Wadt style basis sets........................................................................................43
II.3 .4 Popu lation ana lysis and electron densities........................................................................43VI Table o f Conten ts
Chapter III
Experi mental procedures ...............................................................................................................45
III.1 Chemic als and m ethods....................................................................................................46
III.1 .1 Subs trates a nd so lutions pro cessing................................................................................46
III.1 .2 S yntheses.....................................................................................................................48
III.2 Device de scription.............................................................................................................50
III.3 Computa tional details .......................................................................................................53
Chapter IV
Concentrat ion dependent wavenumber shifts and linewidth changes of C4 H8O in a binary
system (C4H8O+ H2O)..................................................................................................................55
IV.1 Stud y pre sentation and mot ivation...................................................................................55
IV.2 Experi mental and theoretic al considerations ....................................................................57
IV.2 .1 Exper imental details.....................................................................................................57
IV.2 .2 Ab initio calculations of optimized geom etry fo r THF and its com plexes wi th wate r......... 58
IV.2 .3 Var iation of peak positions with concentration for (C-O) and (C-C) mo des...................59
-1
IV.2 .4 Concen tration d ependence of wavenumber shifts in the 975-1100 cm region..................62
-1
IV.2 .5 Concen tration d ependence of mber shifts and vibrational d ephasing of ~896 cm
mode......................................................................................................................................63
IV.3 Conclusions .......................................................................................................................66
Chapter V
Food additives character ization b y Ram an, surface- enhanced Raman spectroscop y, and
theoretical studies ..........................................................................................................................67
V.1 Food additives: w hat are the y and why are the y necessar y?..............................................68
V.2 Tartraz ine (E102) ...............................................................................................................71
V.2.1 Mol ecule presentation....................................................................................................71
V.2.2 Geo metry op timization...................................................................................................72
V.2.3 Vibrational sp ectroscopy................................................................................................74
FT-Raman spe ctrum o f E102 solid s tate...............................................................................74
Raman spe ctra of E102 solutions.........................................................................................75
pH dep endence Raman spectra............................................................................................76
SERS s pectra of E102.........................................................................................................78
V.2.4 Conclus ions...................................................................................................................80
V.3 Sodium benzoate (E211) ....................................................................................................83
V.3.1 Mol ecule presentation83
V.3.2 Vibrational sp ectroscopy84
V.3.3 Conclus ions92
V.4 Erythrosine B (E127)92
V.4.1 Mol ecule presentation92
V.4.2 Geo metry op timization...................................................................................................94
V.4.3 Elec tronic sp ectroscopy..................................................................................................96
V.4.4 Vibrational sp ectroscopy................................................................................................97
FT-Raman spe ctrum o f so lid state Er yB...............................................................................97
Micro-Raman spectra o f EryB solutions98
SERRS sp ectra of EryB.....................................................................................................100
pH dep endence SERRS spectra o f EryB .............................................................................107
V.4.5 Conclus ions.................................................................................................................109
V.5 Indigo carmin e (E132)110
V.5.1 Mol ecule presentation110
V.5.2 Geo metry op timization.................................................................................................111
V.5.3 Elec tronic sp ectroscopy.