PowderDiffraction: A powder may be composed of many small andfinely ground crystals, known as crystallitesThese crystallites are (assumed to be) randomlyorientedtooneanother.SingleCrystalPolycrystallinePowder
Powder Diffraction • A powder may be composed of many small and finely ground crystals, known as crystallites. • These crystallites are (assumed to be) randomly oriented to one another
In the Debye-Scherrer photographic method, a filmwas wrapped around the inside of a X-ray camera.Powder MethonIncidentbeamSpecimenFilm
In the Debye-Scherrer photographic method, a film was wrapped around the inside of a X-ray camera
Powder diffractionpowderedsampleX-rays(a)powderedsampleX-rays(b)Figure 3.3 (a) Cones produced by a powder diffractionexperiment; (b) Producing a powder diffraction photograph
Powder diffraction Figure 3.3 (a) Cones produced by a powder diffraction experiment; (b) Producing a powder diffraction photograph
Examples of Miller indices(100)(111)(c)a(b)(d)(200)(110)
(100) (111) (200) (110)
Families of planes Miller indices describe the orientation aspacing of a family of planes- The spacing between adjacent planes in afamily is referred to as a d-spacingThree differentfamilies ofplanesd-spacing between(300) planes is onethird of the (100)spacing(200) (300)(100)