H型偶氮苯分子—階超極化率的理論研究.pdf

1、東南大學碩士學位論文H型偶氮苯分子—階超極化率的理論研究姓名：褚豐申請學位級別：碩士專業(yè)：物理電子學指導教師：崔一平呂昌貴20080125朱I串』人學傾卜警位論義TheoreticalStudyofH—shapeAzobenzene，F(xiàn)irst—orderHypelpolarizabilitiesAbstractTheconfigurationsofH—shapeazobenzenesandcorrespondingazobenzene

2、monomershavebeenoptimizedbyHartree—FockmethodandDensityFunctionTheory(DFT)Basedonoptimizedconfigurations，CoupledPerturbedHartree—Fock(CPHF)methodwasusedtoobtainfifstorderhyperpolarizabilitiesTheresultsshowedthatH—shapeaz

3、obenzenes’firstorderhyperpolarizabilitiesweretwicelargerthancorrespondingazobenzenemonomers’。ThereasonwasthattherewereintramolecularinteractionsinH—shapeazobenzenes，includingcoulombrepulsions，dipoledipoleinteractionsandh

4、yperconjugatedeffectsComparedwi啦correspondingazobenzenemonomers，coulombrepulsionscouldbreaktheplanaritiesandweakentheabilitiesofchargetransferandtheycouldalsoinduceblue，shiftDipoledipoleinteractionsandhyperconjugatedeffe

5、ctscouldinduceredshift。ThelattertwofactorslastlyovercamecoulombrepulsionswhichexplainedthatH—shapeazobenzenes’firstorderhyperpolarizabilitiesweretwicelargerthancorrespondingazobenzenemonomers’Thecalculatedresultswerecons

6、istentwiththeexperimentalresultsBecausethemeasurementsoffirstorderhyperpolarizabilitiesoforganicmoleculeswerealwaysdoneinthesolventOnsagermodelwasusedtoinvestigatesolventeffectsonfirstorderhyperpolafizabilitiesTheresults

7、showedthatsolventeffectscouldinducetheirredshiftandstrengthentheirfirstorderhyperpolarizabilitiesbecauseallthetransitionsofazobenzenemonomersandH—shapeazobenzeneswere7tTttransitionsBecausetherewereintramolecularinteracti

8、onsinH—shapeazobenzenesthestrengthoffirstorderhyperpolarizabilityofHshapeazobenzenewasmuchlargerthanthatofcorrespondingazobenzenemonomerSolventeffectscouldstrengthenthetrendthatHshapeazobenzenes’firstorderhyperpolarizabi

9、litiesweretwicelargerthancorrespondingazobenzenemonomers’Keywords：H—shapeazobenzene，azobenzenemonomerfirstorderhyperpolarizabilityintramolecularinteraction，coulombrepulsion，dipole—dipoleinteraction，hyperconjugatedeffects