Radium Selenide

Description

Radium selenide has the molecular formula of RaSe and the molecular weight of 304.984985 g/mol. It has the CAS number of 23320-14-1. It reacts with water so that an aqueous method of precipitation cannot be used to prepare this compound. Radium selenide is very moisture sensitive, and must be handled under inert conditions. It can be prepared by reaction of the oxide or carbonate with Se, or by the reduction of the selenate with hydrogen gas:
2RaO+ 3Se ? 2RaSe+ SeO2
2RaCO3 + 5Se+ Heat ? 2RaSe+ 3SeO2 + CO2
RaSeO4+ 4H2 ? RaSe+ 4H2O
Radium selenide is expected to have a simple cubic structure but the crystal lattice parameters have never been published.

The Uses of Radium Selenide

RaSe has been used in the past (1920s–1930s) in the treatment of certain types of cancer, primarily mammography where it was injected directly into tissue.