Stabilization of WVI in nitride environment via acid/base reactions, and general route to layered transition metal nitrides*

DIFT calculations for two hypothetical ternary nitrides of hexavalent tungsten: LaWN3 and La2WN4 (in perovskite and K2NiF4 structures, respectively) show that these compounds should spontaneously form from WN2 (acid) and LaN (base) reagents, or simply from (WN + 1/2 N-2 or W + N-2) and LaN, at ambient or elevated temperature and high N-2 pressure to speed up the reactions. This concept may be utilized to stabilize other Re-VII,Os-VIII efemeric nitrides, like these of Re-VII Os-VIII, and possibly even of unprecedented Ir-IX. La2WN4 is example of rare two-dimensional nitride materials. Band structure calculations confirm that LaWN3, La2WN4 and several related compounds should exhibit metallic conductivity, and they show good prospect for 2D superconductivity via self-doping.