Europium dichloride
# Europium dichloride

Europium dichloride is an inorganic compound with a chemical formula $EuCl_2.$ When it is irradiated by ultraviolet light, it has bright blue fluorescence.

## Production

Europium dichloride can be produced by reducing europium trichloride with hydrogen gas at high temperature

    2 $EuCl_3$ + $H_2$ → 2 $EuCl_2$ + 2 HCl

If dry europium trichloride reacts with lithium borohydride in THF, it can also produce europium dichloride：

    2 $EuCl_3$ + 2 $LiBH_4$ → 2 $EuCl_2$ + 2 LiCl + $H_2↑$ + $B_2H_6↑$

## Properties

Europium dichloride can form yellow ammonia $complexes:EuCl_2•8NH_3,$ and can dissolve to pale yellowish $EuCl_2•NH_3.$ Europium dichloride can react with europium hydride at 120-bar $H_2,$ producing EuClH that fluoresces green.

