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The Molecular Photophysics of Chlorophyll : a Study of Its Triplet State

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The Molecular Photophysics of Chlorophyll : a Study of Its Triplet State THEMOLECULA R PHOTOPHYCICS OF CHLOROPHYLL A STUDY OF ITSTRIPLE T STATE CENTRALE LANDBOUWCATALOQUS OOOO 0086 9574 Ditproefschrif tme tstellinge nva n JOHAN FREDERIKKLEIBEUKE R doctorandus ind echemie ,gebore nt eGroninge no p1 9februar i 1948,i sgoed - gekeurd doord epromoto rdr .T.J .Schaafsma ,hoogleraa r ind emoleculair e fysica. De Rector Magnif-icus van de Landbouahogeschool, J.P.H.va nde rWan t Wageningen, 15 april 1977 A/Al$Zo/ 68? J.F.KLEIBEUKE R The molecular photophysics of chlorophyll A STUDY OF ITS TRIPLET STATE proefschrift terverkrijgin gva nd egraa d vandocto ri nd elandbouwwetenschappen , opgeza gva nd eRecto rMagnificus , dr.ir.J.P.H .va nde rWant , hoogleraari nd evirologie , inhe topenbaa rt everdedige n opvrijda g3 jun i197 7 desnamiddag st evie ruu ri nd eaul a vand eLandbouwhogeschoo lt eWageninge n /r/?- /p¥ 3/f ~* 1.-„ J BIBLIOTHEEK DEI? LANDBOUV/HOOKSCHOOL WAGENINGSN A/A/ 8&os 68^ Stellingen 1 Eenverder e integratie vand emoleculair efysic ai nhe tonderwij se nonder - zoekaa nd eLandbouwhogeschoo lza lee npositiev einvloe dhebbe no pd etoe - passingva nfysisch etechnieke nbi jhe tlandbouwkundigonderzoek . 2 Detoepassin gva nhe texcitonformalism eo pd etriplettoestan dva nchlorofyl - aggregateni sallee ntoegestaan ,indie nd eeffecte nva nd edonor-acceptor - interactiesi nd ebeschouwinge nworde nbetrokken ,zoal sdi too ki sgedaa n doorShipma ne tal .bi jd ebeschrijvin gva nd eabsorptie-spectr ava ndez e molecuulaggregaten. R.H.Clarke ,R.E .Connors ,H.A .Frank ,J.C .Hoch ,Chem .Phys .Lett. , 45,52 3 (1977). L.L.Shipman ,T.M .Cotton ,J.R .Norris ,J.J .Katz ,J .Am .Chem . Soc, 98,822 2 (1976). 3 Inhe tdoo rHuan ge tal .opgesteld emode lvoo rd enulveldsplitsin gva nd e baan-ontaardetriplettoestan dva nmetalloporfyrine se nftalocyanine sword t tenonrecht everondersteld ,da td espin-spininteracti e inall egevalle n kleini st.o.v .d espin-baankoppeling . T.H.Huang ,K.E .Rieckhoff ,E.M .Voigt ,E.R .Menzel ,Chem .Phys. , 29,2 5 (1977). 4 Hetva nelkaa raftrekke nva nspinlabel-ESR-spectra ,gemete nvoo rloodrecht e enparallel eorientati eva nee ngedeeltelij kgeorienteer dmonste rt.o.v . hetmagneetveld ,zoal si stoegepas tdoo rCha oe tal. ,leid tnie tto tee n meerdoorzichtig eanalys eva nd emeetresultaten . Y.Y.H.Chao ,A .Holtzer ,Biochemistry ,J_4 ,216 4(1975) . S Deaanmam eva nShid ae tal. ,da td egrondtoestan dva nhe tmononegatiev e anionva ncoronee ne nva ntrifenylee nnie tontaar dis ,i snie ti novereen - stemmingme texperimente dresultaten ,verkrege nui tMC Dmetingen . T.Shida ,S .Iwatw ,J .Am .Chem .Soc ,95 ,347 3(1973) . P.J.Zandstra ,D.J .Scholtens ,R.E .Koning ,J .Chem .Phys. , _57 3821 (1972). 6 Hetverwaarloze nva nhe t effectva nd ekristalveldsplitsin g opd e liggingva n deenergieniveau s ind e laagstekwartettoestan dva nkoper-octaethylporfin e enee nnie tbeweze naannam eomtren the tkarakte rva nd ekwartet-sub-niveau s leidenShatwel le t al.o pee ndwaalspoo rbi j de interpretatie vand © magnetischgeinduceerd e circulairepolarisati e vand eemissi eva nCtCEP . R.A. Shatwell,R . Gale,A.J .McCaffery ,K .Sichel ,J.Am . Chem. Soc, 97,701 5 (1975). 7 i Deverklaringen ,gegeve ndoo rGafn i etal .e ndoo rBrocho ne tal. ,voo rhe t niet-exponentieleverva lva nd epyridine-nucleotid e fluorescentie,toal sdi e wordt gevondenvoo rhe tvrij ecoenzy mi nvisceuz e oplossinge nvoor!he t eiwit-gebonden coenzym,houde nnie tvoldoend e rekeningme toplosmid^el - reorientatie effecten. A. Gafni,L . Brand,Biochemistry ,^_5 ,316 5 (1976). J.C.Brochon, Ph .Wahl ,J.M . Jallon,M . Iwatsubo,Biochemistry , K5,325 9 (1976). 8 vI nee ndrog eherfs tka nee nkort e strengevorstperiod e dewarmtestr<j>o mva n deaard enaa rd eatmosfee rgedurend e langeretij ddoe nverminderen . 9 ; Detectiegrenzenva n ion-selectieveelektrode n dienenbetrekkin g telliebbe n opd etotal econcentrati e vanhe tbetreffend e ione nnie t opd evrij e ionen- concentratie. Documentatieva nPhilips :Io n selective solid-state electrode for sulfide and silver,typ e IS55 0 S/Ag. Documentatie vanOrion :Guid e to specific ionelectrodes!an d instrumentation. 10 Hetprincipiel e verschil ind ebetekeni sva nhe twoor d trapezium inhe t "Amerikaans-Engels"e n inhe t "Oxford-Engels"ka ngemakkelij k leidento t begripsverwarring. The Concise Oxford Dictionary. Webster's New International Dictionary. Proefschrift vanJ.F .XLeibeuker . Wageningen,me i1977 . Voorwoord Vijfjaa rgeleden ,toe ni knaa rWageninge nkwam ,wa s fotosynthese voormi jee nvolledi g onbekendproce se nwa s chlorophyll eenwa t grootuit - gevallenmolecuul . Zonderd emedewerkin gva nd evakgroe p Plantenfysiologisch Onderzoekbi jmij neerst ekennismakin gme td efotosynthes e end ekenni sva n mijnpromoto rm.b.t .d ebasi sstructuu rva nd e fotosynthetischepigmente n washe tonderzoek ,zoal sbeschreve n indi tproefschrift ,voo rmi jnie tmoge - lijkgeweest . Hetonderzoek ,da t isuitgevoer d ophe tLaboratoriu mvoo rMole - culaireFysic a teWageningen ,wa s alleenmogelij kdankzi jd emedewerkin gva n velenbinne ne nbuite ndez e afdeling.D evel eexperimente nwerde nmogelij k gemaaktdoo rhe tvoorbereiden dwer kva nHenn yva nBeek ,Wille mva nBerkel , dehee rJansen ,Adri ed eJager ,Simo nMaasland ,Jiller tSantem ae nHenn y Zoutendijk,waarvoo r ikaa nalie nmij noprecht edan kwi luitspreken . Bijd eexperimente ne nd edaaro pvolgend ediscussie she b ik altijdvee lsteu ngeha d aand ebelangstellin gva nall emedewerker sva nd e vakgroepMoleculair e Fysica.D emedewerkin gva nRoelo fPlatenkamp ,Pie tGeers e enAri eSonnevel d isonontbeerlij kgewees tvoo rd e afrondingva nhe tonder ­ zoek. Inhe tbijzonde rwi l ikTjeer d Schaafsmabedanken .Hi jinteres - seerdemi jvoo rd e fotosynthese,motiveerd emi jvoo rhe t tripletonderzoe k enwa s tealie ntijd eberei dmi jme traa d endaa d ter zijdet estaan .D evel e discussiesme t jou,Tjeerd ,zij nd e grondslagva nhe tonderzoek ,da tme the t schrijvenva ndi tproefschrif ti safgerond . Tenslott ewi l ikmij nwaarderin guitspreke nvoo rd ewijz e waaropJann y Siebring,d ehee rHoogevee ne nd emedewerkster sva nd e afdeling Tekstverwerkinghebbe nmeegewerk taa nhe t totstan dkome nva ndi tmanuscript . Ikbe nd eNorth-Hollan d Publishing Companyerkentelij kvoo rd etoestemmin g tweei nChemica lPhysic sLetter s gepubliceerde artikelen indi tproefschrif t temoge nopnemen . Contents List of abbreviations 11 Chapter 1 GENERAL INTRODUCTION 13 Chapter 2 STATIC TRIPLET STATE PARAMETERS 18 2.1 INTRODUCTION 18 2.2 THEORY 18 2.2.1 Electronspin ,it sfunction san doperator s 18 2.2.2Th ephysica l concepto fth etriple t state 23 2.2.3 Definitiono fstati c triplet stateparameter s 24 2.2.4Th etriple t stateparameter s inrelatio nt oth e electronic structure 25 2.3 METHODSO FMEASUREMEN T 26 2.3.1 Optical transitions 26 2.3.2Microwav e transitions 27 2.3.2.1 Zerofiel dmagneti c resonance 27 2.3.2.2Hig h fieldmagneti c resonance 27 2.4 REFERENCES 31 Chapter 3 KINETIC TRIPLET STATE PARAMETERS 32 3.1 INTRODUCTION 32 3.2 THEORY 32 3.2.1 Intersystem crossingprocesse s 32 3.2.2 Relaxation 35 3.2.3 Definitionso fzer ofiel dkineti cparameter s 36 3.2.4 Relationbetwee nhig h fieldan dzer o field kineticparameter s 36 3.3 OPTICALELECTRO N SPIN POLARIZATION 38 3.3.1 Signsan dmagnitude so ftriple tES Rpeak s 38 3.3.2 Electronspi n polarizationpattern s 39 3.3.3 Electronspi n polarizationrati o 40 3.4 TIME DEPENDENT HIGH FIELDELECTRO N SPINRESONANC E 42 3.4.1 Principles 42 3.4.2 Mathematical analysis 43 3.4.3 Analogue electronic simulation 46 3.5 REFERENCES 48 Chapter4 THE ELECTRONIC STRUCTURE OF CHLOROPHYLLS AND MODEL SYSTEMS 49 4.1 INTRODUCTION 49 4.2SPECTROSCOPI CCHARACTERIZATIO N 49 4.3THEORETICA LCALCULATION S 50 4.3.1 Freeelectro nmode l 50 4.3.2Th e4-orbita lmode l 51 4.3.3Mor eextensiv ecalculation s 51 4.4REFERENCE S 52 Chapter5 A SPECTROSCOPIC STUDY OF Mg-TETRABENZOPORPHIN I. EXCITED SINGLET STATE PROPERTIES 54 5.1 INTRODUCTION 54 5.2EXPERIMENTA L 55 5.3LIGATIO NO FTH EMAGNESIU MIO N 56 5.4EXCITE DSTAT EPROPERTIE SO FMgTB P 59 5.5DISCUSSIO N 61 5.5.1Effect so fligatio no nelectroni cdistributio n 61 5.5.2Effect so fmolecula rstructur eo nth eequilibriu m constantfo rbiligatio n 65 5.5.3Jahn-Telle reffect s 67 5.5.4S 2-fluorescenc eo fMgTB P 71 5.6CONCLUSION S 72 5.7ACKNOWLEDGEMEN T 72 5.8REFERENCE S 73 Chapter 6 THE TRIPLET STATE OF MgTBP 75 6.1 INTRODUCTION 75 6.2RESULT S 75 6.3DISCUSSIO N 77 6.4REFERENCE S 79 Chapter7 SPIN POLARIZATION IN THE LOWEST TRIPLET STATE OF CHLOROPHYLL 80 7.1 INTRODUCTION 80 7.2EXPERIMENTA L 80 7.3SPI NPOLARIZATIO NWIT HCONTINUOU SILLUMINATIO N 81 7.4TRANSIEN TSPI NPOLARIZATIO N 83 Acknowledgementan dReference s 86 Chapter8 OPTICALLY INDUCED ELECTRON SPIN POLARIZATION IN THE TRIPLET STATE OF CHLOROPHYLL AND ITS MODEL COMPOUNDS 87 8.1 INTRODUCTION 87 8.2EXPERIMENTA L 88 8.3RESULT S 88 8.4 DISCUSSION 90 Acknowledgement and References 91 Chapter 9 THE TRIPLET STATE OF PHOTOSYNTHETIC PIGMENTS I. PHEOPHYTINS 92 9.1 INTRODUCTION 92 9.2MATERIAL SAN DMETHOD S 94 9.3RESULT S 94 9.4DISCUSSIO N 98 9.4.1 ZFSparameter s 98 9.4.2Electro nspi npolarizatio n 104 9.4.3 Kineticparameter s 105 9.5CONCLUSION S 113 9.6REFERENCE S 113 Chapter1 0 PROPERTIES OF THE LOWEST EXCITED TRIPLET STATE OF CHLOROPHYLL 115 10.1INTRODUCTIO N 115 10.2PHOSPHORESCENC EO FCHLOROPHYLL S 115 10.3ZF SPARAMETER SO FCHLOROPHYLL S 116 10.4TRIPLE TSTAT EKINETIC SO FCHLOROPHYLL S 117 10.5CONCENTRATIO NDEPENDENC EO FTRIPLE TSTAT EPARAMETER S 118 10.6SOLVATIO NO FCHLOROPHYLL S 118 10.7GENERA LDISCUSSIO N 120 10.8REFERENCE S 127 Appendices 129 APPENDIXA 129 APPENDIXB 130 Summary 132 Samenvatting 133 10 List of abbreviations AO atomic orbital Bchl bacteriochlorophylla Bph bacteriopheophytina Chia chlorophylla Chib chlorophyllb CI configuration interaction CNDO completeneglec to fdifferentia l overlap ESP electron spinpolarizatio n ESR electronspi nresonanc e FC Franck-Condon FEMR fluorescencedetecte dmagneti c resonance FE free electron HOMO highest occupiedmolecula r orbital IEH iterative extendedHiicke l ISC intersystem crossing LCAO linear combinationo fatomi c orbitals LuTO lowestunoccupie dmolecula r orbital (Mg)TBP (magnesium) tetrabenzoporphin MO molecular orbital MTHF 2-methyltetrahydrofuran Pha pheophytina Phb pheophytinb PMMA.
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