Einsteinium(II) chloride
Einsteinium(II) chloride, with the chemical formula EsCl2, is a binary inorganic compound consisting of einsteinium and chlorine. It is a salt of einsteinium in its +2 oxidation state. Very little is definitively known about the properties of einsteinium(II) chloride due to the extreme radioactivity and scarcity of einsteinium. Studies are hampered by the rapid decay of all einsteinium isotopes and the resulting self-irradiation effects.
It is expected to be a solid at room temperature, though this has not been directly observed. Based on the properties of other actinide dichlorides, it is theorized to have a crystal structure similar to strontium chloride (SrCl2), possibly adopting a fluorite-type structure. It is predicted to be a relatively strong reducing agent.
Due to the difficulties involved in synthesizing and handling einsteinium, EsCl2 has primarily been characterized using theoretical calculations and by inference from the properties of lighter actinide dichlorides such as californium(II) chloride (CfCl2). It is primarily of academic and research interest in the study of actinide chemistry and the behavior of elements at the extreme end of the periodic table. Synthesis would likely involve reducing einsteinium trichloride (EsCl3) with hydrogen gas at elevated temperatures.