Subnitrides are a class of nitrides wherein the electropositive element is in excess relative to the “normal” nitrides.Simon, A. ”Group 1 and 2 Suboxides and Subnitrides — Metals with Atomic Size Holes and Tunnels” Coordination Chemistry Reviews 1997, volume 163, Pages 253–270.
Examples of subnitrides include
Dicyanoacetylene Na16Ba6N features a nitride-centered octahedral cluster of six barium atoms embedded in a matrix of sodium. Boron subnitrides (B13N2, B50N2, B6N)
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