本科毕业论文适合螺旋空穴与碱金属配位结构的理论研究TheoreticalstudyofscrewholeandalkalimetalcoordinationstructureHYPERLINK"http://fanyi.baidu.com/translate"\l"##"学号：学生姓名：指导教师：所在学院：所学专业：二O一五年五月PAGEII摘要近年来，非线性光学(NLO)材料在激光，通讯，电子仪器及医药器材等领域方面得到广泛应用。因此，合成非常好的非线性光学材料吸引了研究者的大量关注。本文通过密度泛函理论方法研究了这种具有扭结体系的结构和非线性光学性质之间的关系。我们选择了一个含有12个交替的吡啶-吡啶低聚物为母体分子，通过在螺旋空穴中分别掺杂两个碱金属原子（锂，钠和钾）设计了三个新分子。主要研究了它们的结构和非线性光学性质之间的关系。三个螺旋化合物Py–pym–2M(M=Li,NaandLi)通过把两个碱金属掺杂到螺旋空穴中被设计。结果表明Py–pym–2Na和Py–pym的结构非常相似，Py–pym–2Na的相互作用能是小于Py–pym–2Li和Py–pym–2K，这表明钠原子的大小和Py–pym化合物的螺旋空穴的尺寸是比较匹配的。关键词：螺旋化合物；螺旋空穴；密度泛函；二阶非线性光学AbstractRecently,considerableattentionshavebeenpaidtosynthesizeexcellentnonlinearoptical(NLO)materials,duetotheirpotentialapplicationsinthefieldofoptoelectronicstechnology.Inpresentwork,weinvestigatetheelectro-opticalpropertiesofsixMöbiusclacenes[n]MC(n=13-18,nisthenumberofbenzenoidrings)andthreehelicalcomplexesyridine-pyrimidine-2M(Py-pym-2M,M=Li,NaandK).weselectalternatingpyridine-pyrimidine(Py-pym)oligomerswithtwelveheterocyclesasparentmolecule,anddesignthreenewcomplexesbydopingtwoalkalimetalsM(M=Li,NaandK)intothehelicalcavitiesofthePy-pymoligomers(Scheme),focusingontherelationshipbetweenthestructureandNLOpropertiesofthepyridine-pyrimidine-2M(Py-pym-2M).Threehelicalcomplexespyridine-pyrimidine-2M(Py-pym-2M)weredesignedbydopingtwoalkalimetalsM(Li,NaandK)intothehelicalcavities.ResultsshowthestructuresofPy-pym-2NaandPy-pymareverysimilar,andtheinteractionenergyofPy-pym-2NaissmallerthanthoseofPy-pym-2LiandPy-pym-2K.ItindicatestheNaatompossessesanappropriatesizetofitinthehelicalcavitiesofPy-pym.Keywords:helicalcomplexe;screwhole;DTF;Second-ordernonlinearopticalsusceptibility目录.TOC\o"1-3"\h\uHYPERLINK\l_Toc12860摘要PAGEREF_Toc12860IIHYPERLINK\l_Toc23026AbstractPAGEREF_Toc23026IIHYPERLINK\l_Toc81911．绪论PAGEREF_Toc81911HYPERLINK\l_Toc321221.1研究现状PAGEREF_Toc321221HYPERLINK\l_Toc247291.2研究内容PAGEREF_Toc247292HYPERLINK\l_Toc259132．理论基