Chemical and Physical Properties of YHg 3 and LuHg 3 .

Amalgams have played an important role in fundamental and applied solid-state chemistry and physics because of the diversity of crystallographic features and properties that they have to offer. Moreover, their peculiar chemical properties can sometimes give rise to unconventional superconducting or magnetic ground states. In the current work, we present an in-depth analysis of single crystals of YHg 3 and LuHg 3 (Mg 3 Cd structure type, space group P 6 3 / mmc ). Both compounds show superconductivity below T c = 1 ± 0.1 K (YHg 3 ) and T c = 1.2 ± 0.1 K (LuHg 3 ). Given the high air-sensitivity and toxicity of these compounds, this study was only possible using a number of dedicated experimental techniques.