This SAED Pattern was taken by Cs-Corrected Scanning Transmission Electron Microscopy?
I would suggest the step-by-step method to index the SAED pattern
(1) measure the diameter, 2R, of each ring using some image processing software such as Image tool, for example. Lets say for the first ring, the 2R = 5.37 [1/nm]
(2) obtain the value of radius, R, (w.r.t central spot); R= 2.68 [1/nm], the unit 1/nm means the distance is in reciprocal lattice
(3) Obtain the interplanar distance (d), in real space, as 1/R; in our case d= 1/R = 1/2.68 =0.372 nm. note that the unit is nm now, as we are talking about real space.
Let us consider my sample is TiO2, I know (by comparsion with d-value of different phases in literature) that a d-value of 0.372 correspond to (101) plan of anatase TiO2.
(4) Now you found the d value for 1 ring. Do the same for procedure to obtain d-values for other rings.
(5) compare the d-value (each of which correspond to a certain set of hkl indices) with the the diffraction data from literature (ICSD data base)
Thereby, you can index the SAED pattern and assign each ring an hkl value. In other words, you can find in which crystalline form your sample is.
Regards.
Take radius of observed circles in image and use inter-planar spacing inversely proportional to R (radius)...calculate ratio of two consecutive circles d spacing and match with d-spacing JCPDS card of silver material.......If you have XRD of these samples then also can be matched with JCPDS data base.................
It looks like in the field of selected area aperture only a few particle was present and diffuse rings would suggest an amorphisation of the material
What size do the particles have? How many particles did you catch with the SAD aperture? I would suggest that the two strong spots should be assigned first, and then you should go on with the diffuse, weaker signals. Make a list with all d-spacings from silver and compare all measured values from the diffraction pattern with your list. If you have measured enough particles and the particles are randomly oriented, you should be able to find almost all d-spacings.
I would suggest the step-by-step method to index the SAED pattern
(1) measure the diameter, 2R, of each ring using some image processing software such as Image tool, for example. Lets say for the first ring, the 2R = 5.37 [1/nm]
(2) obtain the value of radius, R, (w.r.t central spot); R= 2.68 [1/nm], the unit 1/nm means the distance is in reciprocal lattice
(3) Obtain the interplanar distance (d), in real space, as 1/R; in our case d= 1/R = 1/2.68 =0.372 nm. note that the unit is nm now, as we are talking about real space.
Let us consider my sample is TiO2, I know (by comparsion with d-value of different phases in literature) that a d-value of 0.372 correspond to (101) plan of anatase TiO2.
(4) Now you found the d value for 1 ring. Do the same for procedure to obtain d-values for other rings.
(5) compare the d-value (each of which correspond to a certain set of hkl indices) with the the diffraction data from literature (ICSD data base)
Thereby, you can index the SAED pattern and assign each ring an hkl value. In other words, you can find in which crystalline form your sample is.
Regards.
For easy and effective SAED calculations you can explore this link,
http://www.instanano.com/characterization/d-value-calculation/saed-d-value-calculation/
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