Back-reflection Laue Methods Transmission Laue methods In the back-reflection In the transmission Laue ethod, the film is placed etween the laced behind the crystal and the crystal. The beams which are diffracted in a are transmitted through backward direction are the crystal Laue reflections is defined by the transmitted beam emitted beam. The The film intersects the the diffraction spots spots generally lying on ar generally lying on an hyperbola Chemical Crystallography- Single Crystal X-ray Diffraction Single Crystal Analysis at what angles for what orientations of the crystal with .Advantage: You can learn everything to know about the necessarily realize that there is more than one set 0.5mn Stoe IPDs Image plate diffraction System Single Crystal X-ray Diffraction( Cont) X-rays Diffraction Primary application is to determine atomic group, ete mmetry, unit cell dimensions, space struct erfect crystals. I(2 0) of delta function ctly sharp scattering WIL For imperfect crystals, the Thite xray" beam (xrays of variable7) such peaks are broadened that Bragg's equation would be satisfied by For liquids and glasses, it is a numerous atomic planes. ontinuous, slowly varying Modern me ation, Weissenberg tio w slm,function. rotatingeryst setup to X-ray diffraction works on the principle that xrays form limitations of the stationary methods predictable diffraction patterns when interacting with a crystalline matrix of atoms.6 Back-reflection Laue Methods ß In the back-reflection method, the film is placed between the x-ray source and the crystal. The beams which are diffracted in a backward direction are recorded. ß One side of the cone of Laue reflections is defined by the transmitted beam. The film intersects the cone, with the diffraction spots generally lying on an hyperbola. Transmission Laue Methods ß In the transmission Laue method, the film is placed behind the crystal to record beams which are transmitted through the crystal. ß One side of the cone of Laue reflections is defined by the transmitted beam. The film intersects the cone, with the diffraction spots generally lying on an ellipse. Stoe IPDS Image Plate Diffraction System single crystal size < 0.5 mm Chemical Crystallography¾¾ Single Crystal Analysis Single Crystal X-ray Diffraction Single crystal x-ray diffraction is a kind of method by put a crystal in the beam, observing what reflections come out at what angles for what orientations of the crystal with what intensities. ßAdvantage: You can learn everything to know about the structure. ßDisadvantages: You however may not have a single crystal. It is time-consuming and difficult to orient the crystal. If more than one phase is present, you will not necessarily realize that there is more than one set of reflections. Single Crystal X-ray Diffraction (Cont.) ß Primary application is to determine atomic structure (symmetry, unit cell dimensions, space group, etc.,). ß Older methods used a stationary crystal with "white x-ray" beam (x-rays of variablel) such that Bragg's equation would be satisfied by numerous atomic planes. ß Modern methods (rotation, Weissenberg, precession, 4-circle) utilize various combination of rotating-crystal and camera setup to overcome limitations of the stationary methods X-rays Diffraction For perfect crystals, I(2 q) consists of delta functions (perfectly sharp scattering). For imperfect crystals, the peaks are broadened. For liquids and glasses, it is a continuous, slowly varying function. X-ray diffraction works on the principle that x-rays form predictable diffraction patterns when interacting with a crystalline matrix of atoms