Problem 9.8. How far apart are the diffracting planes in a NaCl crystal for which X-rays of wavelength 1.54A make a glancing angle of 15° - 54' in the 1st order?
Data
Glancing angle 0= 15°54' =15+54/60 =15 .9°
Wavelength 1.54Av=1. 54×10-¹⁰m
M =1
To find Distance between diffraction plane ?
Solution
According to relationships for x ray diffraction through crystal
2dsin0 =mA
D = mA/2sin0
D=1×1.54×10-¹⁰ /2sin 15.9°
1.54×10-¹⁰ /2×0.2739. =1.54 × 10-¹⁰/0.5479 =2.81×10-¹⁰m
2.81×10-¹⁰ m ans
