In a paper published in Nature Chemistry this year, researchers created a brand-new helium compound called sodium helide, which is one helium and two sodium atoms.

今年发表在《自然化学》上的一篇论文中说，研究者制造出了一种前所未有的含氦化合物，叫作氦化钠，由一个氦原子和两个钠原子构成。