Crystallography and X-ray diffraction techniques are used to characterize crystals and study their structural properties. X-ray diffraction provides information about crystalline materials by analyzing the diffraction pattern formed when X-rays interact with the crystal structure. Key techniques include X-ray powder diffraction, which can identify crystalline phases and chemical composition in a material, and single crystal X-ray diffraction, which reveals detailed structural information about unit cells. The positions and intensities of peaks in an XRD pattern are unique fingerprints that can be used to identify compounds and study properties like crystallite size.

1. Crystallography
and
XrayDiffraction
characterisationofCrystals

2. Crystallography

3. Crystallography
Studyofcrystals andtheirstructuralproperties.

4. X-rayandCrystals
• X –ray the part of electromagnetic radiation, useful in the
study of crystals.
• Wave length of X ray is matching with the crystal
planes/interplanar distance.
• Hence X ray diffraction is useful in the study of crystals.

5. XRD–xraydiffraction
•X-RayDiffraction,frequentlyabbreviatedasXRD,isa
non-destructivetestmethodusedtoanalyzethestructureofcrystalline
materials.
•XRDanalysis,bywayofthestudyofthecrystalstructure,isusedto
identifythecrystallinephasespresentinamaterialandthereby
revealchemicalcompositioninformation.

6. Single-crystalX-rayDiffraction
• Single-crystal X-ray Diffraction is a non-destructive analytical
technique which provides detailed information about the
internal lattice of crystalline substances,
Including unit cell dimensions, bond-lengths, bond-angles, and
details of site-ordering.

7. XRF-X-rayFluorescenceSpectroscopy
X-ray, generatedinanX-raytube,hitsaninnershell
electronoftheatomandejectstheelectionfromtheatom.
Theopenpositionisfilledbyanelectronfromafurther
outershellandfluorescenceradiationisemitted.

8. WhatisthedifferencebetweenXRDandXRF?
•XRDcandeterminethepresenceandamountsofminerals
speciesinsample,aswellasidentifyphases.
•XRFwillgivedetailsastothechemicalcompositionofa
samplebutwillnotindicatewhatphasesarepresentinthe
sample

9. X ray Powder diffraction Machine.
Powder XRD
XRD
machine

10. XRF Hand Held
spectrometer
XRF gold testing

11. Results

12. XRF–Limits…
TheXRFcannotdetectcommonelementsthatareconsideredtobe
“light”elements,suchasLithium,Beryllium,Sodium,Magnesium,
Aluminium,Silicon,andPhosphorus.

13. EDSanalysis(EnergydispersiveX-rayanalysis)or
energydispersiveX-raymicroanalysis
Itisananalyticaltechniqueusedfortheelementalanalysisor
chemicalcharacterizationofasample.
ItreliesonaninteractionofsomesourceofX-rayexcitationand
asample.

14. Energy-dispersiveX-rayspectroscopy
(EDS)

15. Difference-XRFandEDS
•ThemaindifferencebetweenXRFandEDSistheexcitation
radiation.
•XRFusesanX-raybeamtogeneratecharacteristicX-rays,
• whereasEDSusesanelectronbeam.

16. Xrayproduction
X-raysarecommonlyproducedinX-raytubesbyaccelerating
electronsthroughapotentialdifference(avoltagedrop)and
directingthemontoatargetmaterial(i.e.tungsten).
TheincomingelectronsreleaseX-raysastheyslowdowninthe
target(brakingradiation).

17. XRayGeneration- In an xraytube

18. X-raydiffraction
•X-raydiffractionisbasedonconstructiveinterferenceof
monochromaticX-raysandacrystallinesample.
•TheseX-raysaregeneratedbyacathoderaytube,filteredtoproduce
monochromaticradiation,collimatedtoconcentrate,anddirected
towardthesample.

19. XrayforXRD
•X-raysareusedtoproducethediffraction
patternbecausetheirwavelength,λ,isoftenthesame
orderofmagnitudeasthespacing,d,betweenthecrystal
planes(1-100angstroms).

20. XRDperformance
•Thistestmethodisperformedbydirectinganx-raybeamatasample
andmeasuringthescatteredintensityasafunctionoftheoutgoing
direction.
•Oncethebeamisseparated,thescatter,alsocalledadiffraction
pattern,indicatesthesample'scrystallinestructure.

22. Spacelattice andUnitcell
• Space lattice as a regular three dimensional arrangement of
particles such as atoms , ions or molecules .
• Each particle in the space lattice has the environment or
surroundings as that of any other particles in the lattice .
• Unit cell is the fundamental building block of the crystal .

25. Thesevencrystalsystems

29. BraggsEquation

30. Crystal study -Instrumentation
*deviceforproducingaparallelbeamofraysorradiation.
*

33. XRD XrayDiffractionofcrystals

34. X-raydiffractionorXRD
•X-raydiffractionorXRDisusedforphaseanalysis,crystalline
variants,andtostudythegrainandparticlesizeof
nanomaterials.
•X-raydiffractionspectroscopyasarapidanalysistechniqueis
usedtoidentifythetypeofmaterialaswellasitsphaseand
crystallineproperties.

35. XRD can identify compounds
•XRDcanidentifycompoundsthatcan'tbedetectedbyICP,XRF,or
EDS,suchasnitrates,hydrates,carbonates,andhydroxides.
•XRDcanidentifymultiplecompoundsinthesamesample,and
estimatetheamountofeachtype.

36. Samples preparationforXRD
•UsuallypowderXRD,samplesarepreparedbyhandgrindingusinga
mortarandpestle.
•Themortarandpestlecanbemadeoutofavarietyofmaterialssuch
asagate,corundum,ormullite.

37. XRDdatarepresentation/XRDSpectrum/Diffractogram

38. Tocalculaterelativeintensity
Tocalculaterelativeintensity,dividetheabsoluteintensityofevery
peakbytheabsoluteintensityofthemostintensepeak,andthen
converttoapercentage.
Themostintensepeakofaphaseisthereforealwayscalledthe“100%
peak”.–Peakareasaremuchmorereliablethanpeakheightsasa
measureofintensity.

39. XRDintensitydepends
Thedirectionsofpossiblediffractionsdependonthesizeandshapeof
theunitcellofthematerial.
Theintensitiesofthediffractedwavesdependonthekindand
arrangementofatomsinthecrystalstructure.

40. 2theta inXRD
• This configuration is most convenient for loose powders.
• Thus the 2 θ is the angle between transmitted beam and
reflected beam.
• In an experiment, the transmitted and the reflected beam can
be observed, but the crystallographic plane cannot be
observed, so 2 θ is an experimentally measurable quantity.

41. XRDPeaks
•Peakintensitytellsaboutthepositionofatomswithina
latticestructure.
•peakwidthtellsaboutcrystallitesizeandlatticestrain.

42. Tocheckthenatureofthematerials
UsingXRDpatterns,havetolookthenatureofBragg'speaks
appearingintheXRDpattern.
Ifyougetaverybroadhumpedpeak,thenthematerialwillbe
amorphouswithshortrangeordering.
IfyougetsharppeaksintheXRDpattern,thenthematerialis
crystalline.

44. ParticlesizeinXRD
ParticlesizeisinverselyrelatedtotheFWHM(fullwidth
athalfmaximum)ofanindividualpeak:themorenarrow
thepeak,thelargerthecrystallitesize.

45. WhattheBraggslawtells?
Thelawstatesthatwhenthex-rayisincidentontoacrystal
surface,itsangleofincidence,θ,willreflectbackwithasame
angleofscattering,θ.
And,whenthepathdifference,disequaltoawholenumber,n,
ofwavelength,aconstructiveinterferencewilloccur.

46. XRD -Its limitations
Itismuchmoreaccurateformeasuringlargecrystalline
structuresratherthansmallones.
Smallstructuresthatarepresentonlyintraceamountswill
oftengoundetectedbyXRDreadings,whichcanresultin
skewedresults.

47. d-spacing
Thed-spacingcanbedescribedasthedistancebetweenplanesofatoms
thatgiverisetodiffractionpeaks.
Eachpeakinadiffractogramresultsfromacorrespondingd-spacing.
Theplanesofatomscanbereferredtoa3Dcoordinatesystemandso
canbedescribedasadirectionwithinthecrystal.

48. CopperK-α
CopperK-αisanx-rayenergyfrequentlyusedonlabscalex-ray
instruments.
Theenergyis8.04keV,whichcorrespondstoanx-raywavelengthof
1.5406Å.

49. Copperanodes
Copperanodesarebyfarthemostcommon,sincecoppergives
theshortestwavelengthabove1Å.
Thewavelengthsprovidedby,say,molybdenumandsilverare
normallytooshortformostpowderdiffractionworkinthe
laboratory.

50. PowderXRD (PXRD)
?X-rayPowderDiffraction(XRD),X-raypowderdiffraction(XRD)
isarapidanalyticaltechniqueprimarilyusedforphaseidentificationof
acrystallinematerialandcanprovideinformationonunitcell
dimensions.
Theanalyzedmaterialisfinelyground,homogenized,andaverage
bulkcompositionisdetermined.

51. PhaseanalysisinXRD
Theidentificationofmajorandminorsingleormultiplephasesinan
unknownsampleisthemainapplicationofclassicalX-raypowder
diffraction.

52. Phaseincrystallography
Aphaseisacrystallinesolidwitharegular
3-dimensionalarrangementoftheatoms.
Thisisalsoknownasqualitativephaseanalysis.
Themeasureddiffractionpeakpositionsandintensitiesarelikea
fingerprintofaparticularcrystallinephase.

53. MeaningofPeaksinXRDgraph
Peakintensitytellsaboutthepositionofatoms
withinalatticestructure.and
peakwidthtellsaboutcrystallitesizeandlattice
strain.

54. Latticestrain
Latticestrainisameasureofthedistributionoflatticeconstants,
suchaslatticedislocations,whicharisefromcrystal
imperfections/crystaldefects.

55. ThepositionofthediffractionpeaksinXRD
Thepositionofthediffractionpeaksaredeterminedbythe
distancebetweenparallelplanesofatoms,fromX-raysscattered
byparallelplanesofatomswillproduceadiffractionpeak.

56. XRDpeakintensity
XRDabsoluteintensity(crystallinity)isdeterminedfromthe
strongestdiffractionpeak.
XRDrelativeintensitywascalculatedbydefiningXRDintensity
of(020)peak,ordinarilythestrongestpeak,as100.(Millar
indices)

57. XRDpatternsandparticlesize
Withlargerparticlesize,allthesignalsareobservedanditiseasyto
refinethemaccurately.
If smallparticlesizedmaterials,ofcourseyoucanmaketheXRD
patternsbutyouwillseeverybroadpeaks.
Sometimesyourtwosmallpeakswillbemergedintoasinglepeak.

58. Particle Grain crystallite

60. (Scherrerconstant)
LatticeStrain Dislocationdensity

63. Millerindices
Millerindicesformanotationsystemincrystallographyfor
latticeplanesincrystal(Bravais)lattices.
Inparticular,afamilyoflatticeplanesofagiven(direct)Bravais
latticeisdeterminedbythreeintegersh,k,andℓ,theMiller
indices.

64. Millerindices,calculation
Hereisthe3-stepprocesstofindthemillerindicesforplanes.
1.Findthepointwheretheplaneintersectseachaxis.Iftheplanenever
intersectsanaxisbecauseitisparalleltothataxis,theintersectionpointis
∞.
2.Taketheinverseofeachintersectionpoint.
3.Putthose3valuesintheproper(hkl)format.

65. MillerIndices

66. Millerindex

67. Find Miller Indices

68. Millerindex

69. Millerindex

71. MillerIndex

73. XRDforZnO

74. XRDofgoldnanoparticles

75. XRDpatternofCuOnanoparticles.

77. Calculation ofCrystallite(grain)size fromScherrerEquation

78. Interpretation

84. Mixtureof TiO2 andAl2O3

89. Photo51
Photo51,aclearX-raydiffractionpatternofDNA,showedstructuralfeaturesofDNA
necessaryforscientificunderstandingofDNA´sthree-dimensionalstructure.

90. END…………..