Europium
= Europium
{title2=$\mathrm{Eu}$}
<Europium> is the <chemical element> with <atomic number> 63 and symbol $\mathrm{Eu}$. It is a <lanthanide>. Its $+2$ state is unusually accessible compared with many neighboring lanthanides. Europium ions are used in luminescent materials, where changes in electronic energy are emitted as characteristic colors.<Periodic Table by Royal Society of Chemistry>[Europium, element data and uses]{ref}