The new compound Na x Nb 7 F 2 1 - y Cl y (x ~ 2 ; y ~ 8) synthesized by solid state chemistry crystallizes in the cubic system (space group Pm-3m) with a = 8.2005 (9) 9. The structure has been determined by X-ray diffraction on single crystal ; it is related to that of Nb 6 F 1 5 . However, in the title compound, only one Nb 6 F i 1 2 F a - a 6 2 subnetwork is preserved. The second one is replaced by (NbF 6 ) n - entities. Additional Na + cations provide the cohesion of the structure. We present here this new structure and discuss the possible oxidation states of the single niobium atom inside the (NbF 6 ) n - entities and the valency electron concentration (VEC) of the Nb 6 cluster.