Praseodmium (Pr).

Most of us haven’t heard of this element, yet alone know what is interesting about it!

Praseodmium has been written about elsewhere in this blog. It is one of the rare earth elements and was featured in a series on the rare earth’s around 18 months ago.

What makes it unusual is that it can be made into an alloy by mixing with nickel to form PrN5.1

Nickel, as we all know is magnetic. What is unusual about this alloy is that as it is magnetised, it gets colder (this is known as the magnetocaloric effect2)

It is this unusual property that has been manipulated by scientists in obtaining temperatures close to absolute zero.



Pages sourced at 17:00 BST on Monday 18th June 2012.