The hydrothermal reaction of Na 3 VO 4 , H 3 PO 4 , 2,2':6',2''-terpyridine and water in the mole ratio 2.73:10.1:1.00:1220 provided orange crystals of [VO 2 (terpy)][(VO 2 ) 2 (PO 4 )] in good yield. The structure consists of {(VO 2 ) 2 (PO 4 )} - n n layers with charge-compensating {VO 2 (terpy)} 1 + molecular cations occupying the interlamellar regions. The layer structure consists of a network constructed from chains of corner-sharing {VO 5 } square pyramids, linked through {PO 4 } 3 - tetrahedra. The layer is characterized by cyclic eight polyhedra connects producing sixteen member rings {V 6 P 2 O 8 } which fuse to produce the two-dimensional connectivity. Crystal data: C 1 5 H 1 1 N 3 O 1 0 PV 3 , monoclinic, C2/c, a=12.315(1), b=10.835(1), c=29.181(3) Å, β=101.618(2) o , V=3814.2(6) Å 3 , Z=8, D c a l c =2.010 g cm - 3 .