# Bragg Equation Question

1. Feb 6, 2012

### Dante Tufano

1. Consider a cubic crystal as shown in the figure below. As this single crystal is rotated in an x-ray spectrometer, many parallel planes of atoms besides AA and BB produce strong diffracted beams. Two such planes are shown in the figure.

http://capa.sci.geneseo.edu/p223library/p223Graphics/Gtype02/crystal.GIF

Suppose the wavelength of the x-rays is l = 3.14 nm. Find the angle (with respect to the surface plane AA) of the n = 1 intensity maxima resulting from scattering from planes with spacing d1.

2. Relevant equations

n*λ=2*d1*sinθ

3. The attempt at a solution

So I found the value of d1 using the geometry of the diagram. I tried using the equation to find θ, and got a value of about .065 radians. However, this is apparently wrong. Any ideas on why this isn't right?