Helium as a Nanny

As anyone who took high school chemistry knows, helium is a noble gas, an element too “aloof” to react with others. Turns out that was wrong. New research by UB chemistry professor Eva Zurek and others, inspired by an earlier study that got helium to combine with sodium, indicates that helium might be playing an important role in the formation of stable solid compounds— the myriad combinations of chemical elements that create all kinds of materials. When a compound contains unequal numbers of negatively and positively charged ions (the blue and green circles below), repulsion between them creates instability. Helium can stabilize the compound by inserting itself between the clashing ions, much the way a nanny can settle the back seat of a car by sitting between bickering kids.