資源描述:
《過渡金屬co團(tuán)簇的實(shí)驗(yàn)與理論研究進(jìn)展》由會員上傳分享,免費(fèi)在線閱讀,更多相關(guān)內(nèi)容在教育資源-天天文庫。
1、.山西師范大學(xué)本科畢業(yè)論文過渡金屬Co團(tuán)簇的實(shí)驗(yàn)與理論研究進(jìn)展姓名高娟娟院系化材學(xué)院專業(yè)化學(xué)與材料科學(xué)班級0901學(xué)號0953010145指導(dǎo)教師呂瑾答辯日期成績..過渡金屬Co團(tuán)簇的實(shí)驗(yàn)與理論研究進(jìn)展內(nèi)容摘要過渡金屬團(tuán)簇因?yàn)榫哂懈叽判院透叻磻?yīng)活性,在開發(fā)新磁性材料和新催化劑領(lǐng)域具有廣闊的應(yīng)用前景。實(shí)驗(yàn)上采用Stern-Gerlach技術(shù)【1-4】對Con團(tuán)簇的平均磁距進(jìn)行檢測,從而對團(tuán)簇的磁性特征進(jìn)一步展開研究,研究表明溫度、團(tuán)簇的尺寸大小以及磁場強(qiáng)度這些因素都對Con團(tuán)簇的磁性有重要的影響,并且研究表明團(tuán)簇的磁性與溫度以及磁場強(qiáng)度成正相關(guān)。而磁
2、性隨著團(tuán)簇的尺寸大小的增大先減小后不變,最后穩(wěn)定到體材料的磁矩。理論上先預(yù)測Con團(tuán)簇的基態(tài)結(jié)構(gòu),然后再對團(tuán)簇的磁性進(jìn)行探討,研究表明影響Con團(tuán)簇的磁性的主要因素有對稱性、平均配位數(shù)、平均鍵長。平均鍵長和對稱性與磁性呈正相關(guān),而平均配位數(shù)的大小卻與磁性呈負(fù)相關(guān)。實(shí)驗(yàn)和理論都證明在一定數(shù)目的原子范圍內(nèi)團(tuán)簇的磁性遠(yuǎn)大于體材料的磁性,而超過一定原子數(shù)目以后,團(tuán)簇的磁性逐漸向體材料靠近最后與體材料的磁性相同,這時團(tuán)簇轉(zhuǎn)變?yōu)轶w材料,發(fā)生了質(zhì)的變化?!娟P(guān)鍵詞】: 鈷團(tuán)簇Stern-Gerlach技術(shù)幾何結(jié)構(gòu)電子結(jié)構(gòu)磁性..Experimentalandthe
3、oreticalstudiesoftransitionmetalCoclusterAbstractTransitionmetalclustersbecauseofthehighmagneticpropertiesandhighreactivity,inthedevelopmentofnewmagneticmaterialandnewcatalysthaswideapplicationprospect.Prominentinrecentyearswereintroducedinthispapertheexperimentandtheorycalcul
4、ation,theresearchprogressoftransitionmetalCoclusters,experimentsontheStern-GerlanchdeflectiontechnologyforecastConclustersaveragemagneticspacing,thusfurtherstudyonthemagneticcharacteristicsofclusters,studieshaveshownthatthetemperature,thesizeoftheclusters,andmagneticfieldstren
5、gthofthesefactorstoConmagnetichaveimportantinfluence,Andstudieshaveshownthatclustersofmagneticandtemperature,andpositivelyrelatedtotheintensityofmagneticfield.Andmagneticfirstdecreaseswithincreasethesizeoftheclustersofunchanged,andafterthelaststabletothematerialofmagneticmomen
6、t.IntheorytopredictthegroundstateofConstructure,andthendiscussesthemagneticofclusters,studieshaveshownthatthemainfactorsinfluencingthemagneticofConhavesymmetry,theaveragecoordinationnumber,theaveragebondlength.Averagebondlengthandsymmetryandmagneticwerepositivelycorrelated,whi
7、lethesizeoftheaveragecoordinationnumberandnegativelycorrelatedwithmagnetic.Experimentsandtheoryprovedthatinacertainnumberofatomicclusterswithinthescopeofmagneticfaroutweighmaterialofmagneticbody,andaftermorethanacertainnumberofatoms,magneticclustersgraduallytothematerialnearth
8、eendwiththesamematerialofmagneticbody,thenclustersintomateria