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## Homework Statement

In a particular Low Energy Electron Diffraction (LEED) study of a solid surface, electrons at 45 eV were diffracted at [tex]\phi[/tex] = 53 degrees. Calculate the crystal spacing d.

## Homework Equations

n[tex]\lambda[/tex]=2dsin([tex]\phi[/tex])

[tex]\lambda[/tex] = hc/E

wavelength = c/v

E = vh(n + 1/2)

Note here v is the frequency (nu looked weird on this site)

## The Attempt at a Solution

This questions comes from a problem in my textbook that was a recommended practice problem for an upcoming exam. Despite being an odd numbered problem the answer to it wasn't in the back of the book (figures). Anyways I just wanted to make sure I was solving it correctly.

Firstly I converted the 45 electronvolts into 7.209765E

^{-18}Joules

Then by wavelength = hc/E, i found the wavelength to be 2.754E

^{-8}Meters

Then I found the frequency to be 1.089324619E

^{16}s

^{-1}

Next I found n to be 1/2 (which is weird cause I thought it would be an integer)

Lastly I plugged these values into bragg's law and got 8.623E

^{-9}Meters

Like I said the answer was not in the book for some reason and I'd like to know if I'm doing this right