In chemistry, oxypnictides are a class of materials composed of oxygen, a pnictogen (group-V, especially phosphorus and arsenic) and one or more other elements.
[5] The different subclasses of oxypnictides are oxynitrides, oxyphosphides, oxyarsenides, oxyantimonides, and oxybismuthides.
[2] A drastic increase in the critical temperature was achieved when phosphorus was substituted by arsenic.
Some found in 2008 to be high-temperature superconductors (up to 55 K) of composition ReOTmPn, where Re is a rare earth, Tm is a transition metal and Pn is from group V e.g.
[10] Because of the brittleness of the oxypnictides, superconducting wires are formed using the powder-in-tube process (using iron tubes).