Chemists strike gold, solve mystery about precious metal’s properties
Predicted, actual energy needed for ionization now match
GOLD MINE Chemists have finally explained two of gold’s properties: the energy involved in removing or adding an electron to a gold atom. New theoretical calculations match up with values measured in experiments.
Rob Lavinsky/iRocks.com/Wikimedia Commons (CC BY-SA 3.0)
Gold’s glimmer is not the only reason the element is so captivating. For decades, scientists have puzzled over why theoretical predictions of gold’s properties don’t match up with experiments. Now, highly detailed calculations have erased the discrepancy, according to a paper published in the Jan. 13 Physical Review Letters.
At issue was the energy required to remove an electron from a gold atom, or ionize it. Theoretical calculations of this ionization energy differed from scientists’ measurements. Likewise, the energy released when adding an electron — a quantity known as the electron affinity — was also off the mark. How easily an atom gives up or accepts electrons is important for understanding how elements react with other substances.
“It was well known that gold is a difficult system,” says chemist Sourav Pal of the Indian
