Periodic Table’s Heaviest Elements Alter Theory of Quantum Mechanics

An international team of chemists led by Florida State University researchers has found that the theory of quantum mechanics does not adequately explain how the last 21 elements of the periodic table function. Instead, another well-known scientific theory — Albert Einstein’s Theory of Relativity — helps govern the behavior of these elements.

Periodic table of the elements.

Quantum mechanics are essentially the rules that govern how atoms behave and fully explain the chemical behavior of most of the elements on the periodic table.

But, Florida State University Professor Thomas Albrecht-Schmitt and co-authors found that these rules are somewhat overridden by Einstein’s Theory of Relativity when it comes to the heavier, lesser known elements of the table.

“It’s almost like being in an alternate universe because you’re seeing chemistry you simply don’t see in everyday elements,” Professor Albrecht-Schmitt said.

The team made compounds out of berkelium — a radioactive chemical element with symbol Bk and atomic number 97 — that started exhibiting unusual chemistry.

They weren’t following the normal rules of quantum mechanics.

Specifically, electrons were not arranging themselves around the berkelium atoms the way that they organize around lighter elements like oxygen, zinc or silver.

Typically, chemists would expect to see electrons line up so that they all face the same direction. This controls how iron acts as a magnet, for instance.

However, these simple rules do not apply when it comes to elements from berkelium and beyond because some of the electrons line up opposite of the way chemists have long predicted.

A false-color photomicrograph of the first isolated bulk (1.7 micrograms) sample of berkelium. Image credit: Oak Ridge National Laboratory.

Professor Albrecht-Schmitt and colleagues realized that Einstein’s Theory of Relativity actually explained what they saw in the berkelium compounds.

Under the Theory of Relativity, the faster anything with mass moves, the heavier it gets.

Because the nucleus of these heavy atoms is highly charged, the electrons start to move at significant fractions of the speed of light. This causes them to become heavier than normal, and the rules that typically apply to electron behavior start to break down.

“It was ‘exhilarating’ when we began to observe the chemistry,” Professor Albrecht-Schmitt said.

“When you see this interesting phenomenon, you start asking yourself all these questions like how can you make it stronger or shut it down.”

“A few years ago, no one even thought you could make a berkelium compound.”

The research is published in the Journal of the American Chemical Society.

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Mark A. Silver et al. 2017. Electronic Structure and Properties of Berkelium Iodates. J. Am. Chem. Soc 139 (38): 13361-13375; doi: 10.1021/jacs.7b05569