(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

As a part of a lab report, I need to calculate the distance of the (111) planes of an FCC lattice made out of spheres with diameter D.

2. Relevant equations

3. The attempt at a solution

The course assistant has given me the value of [tex]\frac{\sqrt{6}}{3}D[/tex]. I can understand where the [tex]\sqrt{6}D[/tex] comes from; it's the space diagonal of the cubic unit cell of the FCC lattice. But why is it divided by three? That means that there are three (111)-planes in one unit cell, but I have no idea why is that.

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# Homework Help: Calculating the interplanar distance d111 for an FCC lattice

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