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

Calculate the Madelung constant for an octahedral arrangement of doubly charged anions about a doubly charged cation. Use r0 for the anion−cation distance. (Hint: Remember that the Madelung constant considers the sum of Coulomb interactions over all atom/ion pairs).

2. Relevant equations

Possibly helpful Equations

E_{A}=-(Mke^{2})/r_{0}

α=2M/((n_{1}+n_{2})|Z_{1}Z_{2}|)

E_{A}=-(ke^{2}α(n_{1}+n_{2}(|Z_{1}Z_{2})/2r_{0}

3. The attempt at a solution

So we have a theoretical bond pair X^{+2}Y^{-2}with a coordination number of 6.

I believe the next step should be to calculate E_{A}, but I fail to see how to do that with out α.

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# Homework Help: Calculate the Madelung Constant

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