I The Debye- Sherrer Camera Debye Scherrer Camera A very small amount of powdered material is sealed into a fine capillary tube made from pecimen is placed in the Debye Scherrer camera and is accurately aligned center of the camera. X-rays enter the camera 三 through a collimator. The powder diffracts the xrays in accordance with Braggs law to produce cones of diffracted 16·R ,10 ams.These cones intersect a strip of photographic film located in the cylindrical camera to produce a characteristic set of arcs is diffraction angle, R is radii of camera, 2L is the distance of on the film Debye-Scherrer Camera Powder diffraction film e Can record sections on these cones on film or some When the film is removed from the camera flattened ay of doing holes for the incident and transmitted beams sample with a strip of film Can cov this causes the highest angle back "reflected ares to intensities by electronically scanning film or measuring positions using a ruler and guessing the hole is for the transmitted beam and which is for the relative intensities using a "by eye comparison incident beam in the film X-ray powders Npos Peter Josephus Wilhelmus Debye and diffraction ●制‖‖( centered cubic stru diffraction )●0 Debye-Scherrer powder camera photographs of Zircon (ZrSio Zircon is a fairly complex tetragonal The schematic shows the debve cones that intersect tructure and this complexity is reflected in the tIons asured on the film to determine the d-spacings for diffraction pattern. he reflections measured8 The Debye-Sherrer Camera 2L 180 4 R = p q · · p q = · 180 4 R 2 L q is diffraction angle, R is radii of camera, 2L is the distance of every pair of arcs in the image Debye Scherrer Camera ß A very small amount of powdered material is sealed into a fine capillary tube made from glass that does not diffract x-rays. The specimen is placed in the Debye Scherrer camera and is accurately aligned to be in the center of the camera. X-rays enter the camera through a collimator. ß The powder diffracts the x-rays in accordance with Braggs law to produce cones of diffracted beams. These cones intersect a strip of photographic film located in the cylindrical camera to produce a characteristic set of arcs on the film. Debye-Scherrer Camera Can record sections on these cones on film or some other x-ray detector –Simplest way of doing this is to surround a capillary sample with a strip of film –Can covert line positions on film to angles and intensities by electronically scanning film or measuring positions using a ruler and guessing the relative intensities using a “by eye”comparison 1916 X-ray powders diffraction Powder Diffraction Film ß When the film is removed from the camera, flattened and processed, it shows the diffraction lines and the holes for the incident and transmitted beams. ß There are always two arcs in the x-ray beams Ka and Kb , this causes the highest angle back-reflected arcs to be doubled. From noting this, it is always clear which hole is for the transmitted beam and which is for the incident beam in the film. Dutch post stamp, 1936, memorizing Peter Josephus Wilhelmus Debye and his Nobel prize. ß The schematic shows the Debye cones that intersect the film in the camera, and how diffractions are measured on the film to determine the d-spacings for the reflections measured. Debye-Scherrer powder camera photographs of gold (Au), a Face centered cubic structure that exhibits a fairly simple diffraction Debye-Scherrer powder camera photographs of Zircon (ZrSiO4 ). Zircon is a fairly complex tetragonal structure and this complexity is reflected in the diffraction pattern