Ca6Li1-xFexTe2N3

This phase is grown from the reaction of tellurium and lithium nitride in Ca/Li flux; iron is leached from the steel crucible. A 1:1 mixture of Ca and Li melts at around 300 C and is an excellent solvent for main group metals and sources of light elements such as C, CaH2, and Li3N, enabling the formation of complex carbide, hydride, and nitride phases. This compound is charge-balanced, with one site occupied by a mixture of lithium and iron ions, with iron in the very rare +1 oxidation state. Its structure is a stuffed anti-site variant of the Tl3BiCl6 structure type (tetragonal, space group P42/m); the iron cation (red sphere) is linearly coordinated by nitride anions (yellow). Magnetic measurements indicate the iron has a higher than expected magnetic moment, due to the strong anisotropy of its coordination environment. This is described in our just accepted J. Am. Chem. Soc. manuscript.