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1、PowderX-RayDiffractionX-rayselectromagneticradiationwithwavelengthsbetweenabout0.02Åand100Å.WhenthetargetmaterialoftheX-raytubeisbombardedwithelectronsacceleratedfromthecathodefilament,twotypesofX-rayspectraareproduced.Continuous&characteristicspectracharacteristicspectra,isproducedathighvol
2、tageasaresultofspecificelectronictransitionsthattakeplacewithinindividualatomsofthetargetmaterialBohrmodeloftheatomAnodeKaKaKb12Cu1.54060Å1.54439Å1.39222ÅWhileKbcanbeCr2.289702.293612.08487filteredout,Ka1Fe1.936041.939981.75661andKa2areveryCo1.788971.792851.62079Mo0.709300.713590.63229closet
3、oeachother.Forcarefulwork,DiffractionfromKa2canberemovedbysoftwarecalculation.ThePowderMethodDiffractedBeamIncidentBeamhkl,dvalue,and2θ(calculatedbyBragg’sLaw)1000090008000700060005000Lin(Counts)400030002000100002030405060C2204H3-File:C2204H3.raw-Type:2Th/Thlocked00-005-0628(*)-Halite,syn-Na
4、Cl-Cubic-Face-centeredInstrumentRS:ReceivingSlit(enteredinmm)FDS:FixedDivergenceSlit(enteredindegrees)VDSLength:VariableSlit(mmcorrespondtobeamwidthonsample)FullAxialModel:enterprimaryandsecondarySollerslitsizesPeakposition,peakintensity,peakshapePeakposition,dvalue,hklplanePeakintensity:gri
5、ndedsample?Preferredorientation.Peakshape:semi-crystalline,non-crystal,crystallinedomainsize?Standarddiffractiondatabase:pdffile(powderdiffractionfile)MixtureSamplecompositionRed:Absenceline;Blue:XRDSimulatedPXRDSimulatedpowderX-raydiffractionpatterncanbeobtainedfromsoftware.Checkthepurityof
6、bulkysinglecrystallinesample.(peakpositions)Scherrerequation(OrderedDomainsize)Kistheshapefactor,λisthex-raywavelength,βisthelinebroadeningathalfthemaximumintensity(FWHM)inradians,andθistheBraggangle;τisthemeansizeoftheordered(crystalline)domains,whichmaybesmallerorequaltothegrainsize.Thedim
7、ensionlessshapefactorhasatypicalvalueofabout0.9,butvarieswiththeactualshapeofthecrystallite.Iftheothercontributionstothewidtharenon-zero,thenthecrystallitesizecanbelargerthanthatpredictedbytheScherrerformula,withthe"extra"peakwidthcomingfromtheothe
