Poly[[μ-bis-(4-nitro-phen-yl) phosphato-κ(2) O,O']sodium].

The title compound, [Na(C12H8N2O8P)], consists of one Na(+) cation and one bis-(p-nitro-phen-yl)phosphate anion with a considerable distortion of the phosphate tetra-hedron due to the presence of two P-O ester bonds. The anion bridges five Na(+) cations whereby each cation is chelated by the nitro O atoms of one anion and bonded via a nitro O atom and phosphate O atoms to four other anions. This bridging arrangement leads to the formation of double layers parallel to (001). Adjacent layers are linked through weak C-H⋯O hydrogen bonds.