Conformations and fragmentation of biologically relevant molecules and their binary complexes with water probed by high resolution UV and mass analyzed threshold ionization spectroscopy [Elektronische Ressource] / Rosen Karaminkov

Description

Technische Universitat¨ Munchen¨Physikalische ChemieConformations and Fragmentation of Biologically RelevantMolecules and their Binary Complexes with Water Probed byHigh Resolution UV and Mass Analyzed Threshold IonizationSpectroscopyRosen KaraminkovVollstandiger¨ Abdruck der vonder Fakultat¨ fur¨ Chemieder Technischen Universitat¨ Munchen¨zur Erlangung des akademischen Grades einesDoktors der Naturwissenschaftengenehmigten Dissertation.Vorsitzender: Univ. Prof. Dr. St. J. GlaserPrufer¨ der Dissertation:1. Univ. Prof. Dr. H. J. Neusser2. Univ Dr. Dr. h. c. A. LaubereauDie Dissertation wurde am 09.11.2009 bei der Technischen Universitat¨ Munchen¨ eingereicht unddurch die Fakultat¨ fur¨ Chemie am 07.12.2009 angenommen.2To my lovely daughters,Vanessa and Plamena,and to my beloved wife,Evelina4PrefaceSince the dawn of humanity the permanent desideration for knowledge and understanding ofthe surrounding world has been the driving force that evolved the ancient studies and promotedthe science over the ages to its modern thrive with its complexity and variety of research fields.Nowadays the macroscopic properties and functionality of chemical and biological systems havebeen ultimately related to the microscopic properties of the their constituents thus giving riseto research areas such as spectroscopy, microbiology, nanoscience, etc., with their realms ofinterest, which are closely interwoven.

Informations

• Publié par: technische_universitat_munchen
• Publié le: 01 janvier 2009
• Nombre de lectures: 11
• Langue: English
• Poids de l'ouvrage: 14 Mo

Extrait

TPhechnischeysikalischeUniversit¨atChemieM¨unchen
ConformationsandFragmentationofBiologicallyRelevant
HighMoleculesResolutionandtheirUVandBinaryMassComplexesAnalyzedwithThrWesholdaterProbedIonizationby
oscopySpectr

orsitzender:V

Dissertation:derufer¨Pr

voKaraminkRosen

Vollst¨andigerAbdruckdervon
derFakult¨atf¨urChemie
derTechnischenUniversit¨atM¨unchen
zurErlangungdesakademischenGradeseines
DoktorsderNaturwissenschaften
Dissertation.genehmigten

Univ.-Prof.Dr.St.J.Glaser

1.Univ.-Prof.Dr.H.J.Neusser
2.Univ.-Prof.Dr.Dr.h.c.A.Laubereau

DieDissertationwurdeam09.11.2009beiderTechnischenUniversit¨atM¨uncheneingereichtund
durchdieFakult¨atf¨urChemieam07.12.2009angenommen.

2

Tomylovelydaughters,

Plamena,andanessaV

and

to

edvbelomy

elinaEv

wife,

4

efacePr

Sincethedawnofhumanitythepermanentdesiderationforknowledgeandunderstandingof
thesurroundingworldhasbeenthedrivingforcethatevolvedtheancientstudiesandpromoted
thescienceovertheagestoitsmodernthrivewithitscomplexityandvarietyofresearchfields.
Nowadaysthemacroscopicpropertiesandfunctionalityofchemicalandbiologicalsystemshave
beenultimatelyrelatedtothemicroscopicpropertiesofthetheirconstituentsthusgivingrise
toresearchareassuchasspectroscopy,microbiology,nanoscience,etc.,withtheirrealmsof
interest,whicharecloselyinterwoven.Aniceexampleofcollaborationbetweentherapidlyde-
velopingbranchesofscienceistheconnectionbetweenstereochemistryandspectroscopy.While
theformerdealswithspatialarrangementsofatomsinmoleculesandtheeffectsofthesearrange-
mentsonthephysicalandchemicalpropertiesofsubstances,spectroscopyprovidesinsightinto
thestructureandbondingofthemostabundantisomersofachemicalcompound.
Theuniqueconditionsobtainedduringthesupersonicexpansionofmoleculesfromhigherpres-
sureintovacuumresultsintheformationofcoldmoleculesandsmallcomplexeswhichsome-
timeshavebeenreferredtoasthoseofafourthstateofmatter.Furthermore,inmolecularbeams,
thespeciesconcernedcanbeinvestigatedunderconditionsthatremovedpressurebroadening
andmuchofDopplerbroadeningfromtheresultingspectra.Whenmoleculesareinjectedinto
thecarriergas,theyattainverylowrotationaltemperatures,highervibrationaltemperaturesof
theorderof100Kandtranslationaltemperaturesdownto0.1K.Therefore,theso-calledfourth
stateofmatterconsistsofmoleculeswhicharegenerallycoldandwhichhavedifferenttrans-
lational,rotationalandvibrationaltemperatures.Theseconditionsareanexcellentenvironment
formolecularspectroscopyandresultinseveralmajoradvantages.First,weaklyboundspecies,
suchasvanderWaalsandhydrogen-bondedcomplexesandclusters,areheldtogetheratthe
typicallylowvibrationaltemperature,whichallowsahighprecisionspectroscopicstudiesand
secondadvantageisthatspectraoflargemoleculescanberotationallyresolved.Thedevel-
opmentoflasersandtherefinementofthemassresolutiontechniqueshavebeenprovedtobe
anextremelyimportanttoolininvestigationofthespectroscopy,conformations,fragmentation
anddynamicsofmoleculesinsupersonicjetsorpulsedbeams.Themassanalyzedthreshold
ionizationandresonanceenhancedtwophotonionizationtechniques,usedinthiswork,have
demonstratedtheabilitytoobtainbeautifulelectronicspectraevenfortheverylowconcentra-

5

6

thetionslasertypicalresolutionofsobiologicalhighthespeciesspectraincoldofevensupersonicquitejets.complexorBecauseganicthemoleculessamplesarebecomesocoldsimpleand
genenoughbondstoandanalyzehinydrogenbondeddetail.Conformerscomplexesstabilizedareoftroughinteresttheparticularlyformationofinintrabiochemicalmolecularhsystemsydro-
andreactions.alsoforItaisvarietysignificantofotherthatinreasons;thepastfore30xample,years,atheydetailedmaybepictureintermediatesofhydrogenininterbondingmolecularhas
mergedfromhigh-resolutionandmassselectivespectroscopyinvestigationsofweaklybounded
es.xcomple

Contents

Preface

oductionIntrI

3

13

15oductionIntr11.1Molecularconformers................................15
1.2Hydratedcomplexes................................17
1.3Photofragmentationofbiomolecules........................18

DetailsExperimentalII

21

23echniquesTExperimental22.1ResonanceEnhancedTwo-PhotonIonization(R2PI)UVLaserSpectroscopy..24
2.2R2PIExperimentalSetup.............................25
2.2.1Molecularbeamapparatus.........................25
2.2.2LaserSystem................................28
2.2.3ControloftheExperiment.DataAcquisitionSystem...........32
2.3GeneticAlgorithm.................................32
2.4Mass-AnalyzedThresholdIonization(MATI)...................34
2.4.1MATIExperimentalSetup.........................35

DiscussionandResultsIII

37

3ConformationalStructuresof2-PhenylethanolanditsHydratedComplex39
3.1Introduction.....................................40
3.2ExperimentandDataProcessing..........................41
3.3ExperimentalResults................................42

7

8

4

5

6

CONTENTS

3.3.1LowResolutionSpectrum.........................42
3.3.2HighResolutionSpectra..........................43
3.3.3MonomerBands..............................43
3.3.4WaterComplexBands...........................46
3.4AbinitioCalculations................................48
3.4.12-PEMonomer...............................48
23.4.22-PE∙HOComplex.............................51
3.5Discussion......................................53
3.5.1Monomerconformers............................53
3.5.22-PE∙HOConformer............................56
23.6SummaryandConclusions.............................59

High-ResolutionUVSpectroscopyof2-para-uorophenylethanol61
4.1Introduction.....................................62
4.2ExperimentandDataProcessing..........................63
4.3ExperimentalResults................................64
4.3.1LowResolutionSpectrum.........................64
4.3.2HighResolutionSpectra..........................65
4.3.3AbinitioCalculations............................69
4.4Discussion......................................70
4.5SummaryandConclusions.............................75

MassAnalyzedThresholdIonizationSpectroscopyof2-para-uorophenylethanol77
5.1Introduction.....................................79
5.2Experimental....................................79
5.3Results........................................80
5.3.1REMPIspectra...............................80
5.3.2MATIspectra................................80
5.3.3Computationalresults...........................83
5.4Discussion......................................86
5.5Summaryandconclusions.............................90

ConformationalProbingof2-ortho-uorophenylethanol93
6.1Introduction.....................................94
6.2Experiment.....................................95
6.3Results........................................96
6.3.1LowResolutionSpectrum.........................96
6.3.2HighResolutionSpecta..........................97
6.3.3AbinitioCalculations............................102

CONTENTS

9

6.4Discussion......................................105
6.5Summaryandconclusions.............................110

7WaterClustersof2-para-uorophenylethanoland2-ortho-uorophenylethanol113
7.1Introduction.....................................114
7.2ExperimentandDataProcessing..........................114
7.3ResultsandDiscussion...............................115
7.3.12-pFPE-WaterCluster...........................115
7.3.22-oFPE-WaterCluster...........................124
7.4SummaryandConclusions.............................130

8R2PIMassSpectroscopyofEphedrine133
8.1Introduction.....................................134
8.2Experiment.....................................134
8.3Results........................................135
8.3.1Abinitiocalculations............................135
8.3.2Experimentalresults............................136
8.4Discussion......................................138
018.4.1Benzene-likeS←Sspectrum.......................138
8.4.2Fragmentationpathways..........................139
8.4.3State-selectivefragmentation........................141
8.5Summaryandconclusions.............................143

9Pseudoephedrine:EvidenceforConformerSpecificFragmentation145
9.1Introduction.....................................146
9.2ExperimentandDataProcessing..........................146
9.3Results........................................147
9.3.1AbinitioCalculations............................147
9.3.2Low-ResolutionSpectra..........................147
9.3.3High-ResolutionSpectra..........................148
9.4Discussion......................................155
9.5SummaryandConclusions.............................156

ConcludingIVemarksR

ppendicesA

159

163

167InteractionsolecularMAA.1ChemicalBonds...................................167

10

CONTENTS

A.2WeakMolecularInteractions............................168
A.2.1AttractiveMolecularInteractions.....................168
A.2.2RepulsiveMolecularInteractions.....................170
A.3TheConceptofWeakMolecularBonds......................170
A.4ClassificationofWeakMolecularBonds......................172
A.4.1HydrogenBonds..............................172
A.4.2Quadrupole-QuadrupoleBonds......................175
A.4.3Charge-TransferBonds...........................175
A.4.4Ion-MediatedBonds............................175