Solving Solid State Physics: Max Wavelength of Po Crystal Diffraction

[kel]

Homework Statement

The element Po forms a crystal with a simple cubic structure of spacing
(3.34A). What is the maximal wavelength of radiation that is diffracted from a powder of that crystal

Homework Equations

N/a, however I thought that it may well be something to do with the bragg equation i.e 2d sin(angle) = n*wavelength

The Attempt at a Solution

I had started using the bragg equation, but it's fairly obvious to see that I need to have the angle of incident/reflection also in order to find the wavelength.

As this is the first time that I have had any experience of solid state, I'm really not quite getting it - probably just me.

Could you suggest where I may be going wrong i.e. am I using the wrong equation for this question? and could you suggest a starting point.

I guess that I need to use some feature of the cubic structure in order to calculate this, but I'm a bit lost.

Thanks
Kel

 

[Kurdt]

The question asks for the maximum wavelength and so all you have to do is think of what sin theta will give you the largest value.