Two ions, and , have ionic radii of and respectively, in a close-packed AB crystal compound. What is — Solid State Chemistry Question

💡 Solution & Explanation

The radius ratio is calculated as $\frac{r_+}{r_-} = \frac{86}{200} = 0.43$. This value falls strictly in the range of $0.414 \le \frac{r_+}{r_-} < 0.732$, which corresponds to an octahedral geometry. Therefore, the coordination number of the cation is 6.