溴化鉀團(tuán)簇的相變和成核的分子動(dòng)力學(xué)模擬.pdf

1、索取號(hào)：Q鯉3：11Z2呈Q密級(jí)：二越南京坪勉犬掌碩士學(xué)位論文園溴化鉀團(tuán)簇的相變和成核的分子動(dòng)力學(xué)模擬作者：院系：指導(dǎo)教師：學(xué)科專業(yè)：陳凱化學(xué)與環(huán)境科學(xué)學(xué)院朱小蕾教授物理化學(xué)南京師范大學(xué)碩士學(xué)位論文：溴化鉀團(tuán)簇的相變和成核的分子動(dòng)力學(xué)模擬MoleculardynamicssimulationsofphasetransitionandnucleationofKBrclustersAbstractSincethephasetransitio

2、nandnucleationaremicroscopicprocesses，theexperimentalstudyoftheseprocessesiSdi伍cultDespitetheobviOUSimportanceofphasetransitionandnucleationinscienceandtechnologythereisnotmuchknowledgeaboutthedetailsofatomicormolecularp

3、rocessesinsuchtransformationsOntheotherhand，computersimulationprovidesadirectroutefromthemicroscopicdetailsofasystemtomacroscopiepropertiesofexperimentalinterestMoleculardynamicssimulationsareperformedon(KBr)10s，(KBr)256

4、，(KBr)s00，and(KBr)s64clusterstoanalyzestructural，energetic，andkineticaspectsofphasetransitionBomMayerHugginspotentialfunctionWaSemployedtoreproducemeltingandfreezingwhenclustersareheatedandcooledVariOUSdiagnosticmetho出in

5、cludingthetotalenergycurves，theLindemannindices，andpair—correlaftonfunctions，areusedtocharacterizephasechangesduringheatingandcoolingstagesResultsdemonstratethatthemeltedclustersarenotsphericalinshapeThemeltingtemperatur

6、esandheatsoffusiondecreaseapproximatelylinearlywiththereciprocalsofclusterradii耵1cmeltingpointandheatoffusionforbulkKBrobtainedbyextrapolationareclosetotheexperimentalvaluesOntheotherhandⅡlehomogeneousnucleationinthefree

7、zingofmoltenclusterscomprisedof256，500and864KBrionpairshavebeeninvestigatedincomputersimulationThenucleationratestendtodecreasewithincreasingclustersizeandtemperaturenlcsolid—liquidinterfacial丘eeenergy盯。of424523mJ／m2iScl

8、osetothevaluespredictedbyTurnbull’SrelationandcomparabletotheexDerimentalobservationbyBuckleandUbbelohdeSizesofcriticalnucleiinferredfromclassicalnucleationtheoryareof65—207KBr—ionicpairsinthetemperaturerangeof400600KThe