The lengthof a unit cell in the NI Crystal is 0.352 nm. The diffraction of X-rays of 0.154 nm wavelength (lambda) from a Ni crystal occurs at 22.2^(@), 55.9^(@) and 38.2^(@) . By using Bragg's law, (nlambda=2d "sin"theta) , and assuming that the diffractions are first order (n=1), the distance are calculated to be 0.204 nm , 0.176 nm and 0.124 nm The various structures for the Ni crystal are represented as: The distance (d) of 0.204 nm represent which structure?

The lengthof a unit cell in the NI Crystal is 0.352 nm. The diffractio

1.	The lengthof a unit cell in the NI Crystal is 0.352 nm. The diffraction of X-rays of 0.154 nm wavelength (lambda) from a Ni crystal occurs at 22.2^(@), 55.9^(@) and 38.2^(@) . By using Bragg's law, (nlambda=2d "sin"theta) , and assuming that the diffractions are first order (n=1), the distance are calculated to be 0.204 nm , 0.176 nm and 0.124 nm The various structures for the Ni crystal are represented as: The distance (d) of 0.204 nm represent which structure?
Answer» I II III All Solution :The distance 0.204 pm comes out to be" `a//sqrt(3)"` which CORRESPONDS to the perpendiucular distance between a corner of UNIT cell and the plane of the THREE adjacent CORNERS. (FIG III) .