Download presentation

Presentation is loading. Please wait.

Published byRonan Holly Modified over 2 years ago

1
Sai Nandyala

2
Determination of crystal structure internally Every lattice plane behaves like a diffraction grating when X-rayed Position of spectral likes depend on distance between lines and so the nature of X-ray depends on the spacing between planes

3
(pic 5.1) Monochromatic xrays FCD, FC’D, FC’’D are path lengths FC’D is larger than FCD by AC’B AC’B = 2AC = 2dsin# N(lamda) = 2dsin# Bragg’s Equation N-integral number lamda – wavelength (Eq of f) F = sf = mean amp. Of waves scattered W(r) = prob. Of finding e- bw two shells

4
Laue Photographic Method Rotating Crystal Method Oscillating Crystal Method Powder Method

5
Tiny crystal on narrow incident beam from filament to diff beam on p plate Laue pattern appears #, d(spacing), is found (pic)

6
Beam penetrates at 90” where crystal rotates on axis // to axes During rotation, diff positions show diff spots on p plate (pic) Terms of layer lines

7
Crystal at 10” to 20” Reflecting positions exposed and is lim. Cylindrical p plate

8
Powdered samples Beam to powder to diff ray to strip to diff rings Simplest to work Work when crystals uneasy to get (pic)

9
Identify crystaline phases and orientations Determine atomic arrangement Measure thickness of films Determine structural properties

Similar presentations

© 2017 SlidePlayer.com Inc.

All rights reserved.

Ads by Google