GATE MT 2020 Q10. X –ray diffraction pattern from an elemental metal with a FCC crystal structure shows the first peak at a Bragg angle 24.65 degrees. The lattice parameter of this metal is ___nm. Given, wavelength of the X-ray used is 0.1543 nm.
GATE MT 2020 Q10. X –ray diffraction pattern from an elemental metal with a FCC crystal structure shows the first peak at a Bragg angle 24.65 degrees. The lattice parameter of this metal is ___nm. Given, wavelength of the X-ray used is 0.1543 nm.
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By following the relationship between lattice parameters and interplanar distance , also using the Bragg's law we can solve this as shown.
By following the relationship between lattice parameters and interplanar distance , also using the Bragg’s law we can solve this as shown.
See lessAccording to Bragg’s law, Since, reflection is coming from 1st peak of FCC. Hence plane will be (111). by putting, λ (wavelength of Xray) = 0.154 nm, Ɵ (bragg’s angle) = 24.5˚ We will get => a = 0.32 nm Some of you might be thinking why (111) plane correspond to the 1st peak which givesRead more
According to Bragg’s law,
Since, reflection is coming from 1st peak of FCC. Hence plane will be (111).
by putting, λ (wavelength of Xray) = 0.154 nm, Ɵ (bragg’s angle) = 24.5˚
We will get => a = 0.32 nm
Some of you might be thinking why (111) plane correspond to the 1st peak which gives refelction for FCC.
So, For a specific crystal which plane will give refelction and observed in the output of XRD result is guided by some criteria. Those criterias are established by sturcture factor calculation.
Correct answer is option D. @Career Avenues described it best. Thank you.
Correct answer is option D. Career Avenue Avenues described it best. Thank you.
See lessa=0.32nm
a=0.32nm
See less0.320 nm
0.320 nm
See less