# Homework Help: X ray diffraction For crystal structure Analysis

1. Sep 10, 2007

1. Find the crystal structure , the lattice parameter of the metal.
Known 2$$\theta$$ of the peaks
17
21
28
33
35
41
45
46

2. bragg's law $$\lambda$$=2 d$$_{h,k,l}$$ /b]sin$$^{2}$$($$\theta$$)
Also, the cubic interplanes distance d$$_{h,k,l}$$ = a0/(squr(h$$^{2}$$+k$$^{2}$$+l$$^{2}$$)

3. The attempt at a solution:
Since I didn't know the lattice parameter I just take the sin$$^{2}$$ of every theta and the divide every number between the smallest number, (the first peak one), to get integers. According to that I should know which cubic structure is( BCC FCC SC) What's happens is that I get the following numbers with all the procedure 4,6,12,14,16,22,26,28. I can't identify which one is.

Thanks for any help.

Last edited: Sep 10, 2007