Some elements go cubic under pressure

An item in the August 2007 Physics Update section states that “polonium, with atomic number 84, is the only element with a simple cubic crystal structure.” In the 21st century, that statement is a bit extreme.

Selenium, in the same element group as polonium, has an allotrope ¹ with simple cubic structure, as described in a text by Jerry Donohue. ² Perusal of his book will also illuminate simple cubic structures of other elements.