theoretical chemistry - Do ions also form special electron configurations? (just as Copper and Chromium do)

Do ions also form special electron configurations? (just as Copper and Chromium do)

I know that because copper has 1 electron in its s-orbital (highest) because it wants to have a full d-orbital (d^10)

But do ions also act this way?

Answer

Check out the NIST database for electronic configurations for atoms and ions in the gas phase. If you play around a bit, you will find that yes, some ionizations will not follow the expected trends from the aufbau principle. For example, search for rhenium and compare the configurations between $\ce{Re^{11+}}$ and $\ce{Re^{17+}}$, and you'll see some of them are unexpected (and rather hard to explain). Osmium shows an anomaly going from $\ce{Os^{+}}$ to $\ce{Os^{2+}}$. There are other elements with ions containing aufbau anomalies, but I can't remember many from the top of my head.