Two polyoxometalate open framework (POMOF) materials have been synthesized using a secondary building unit (SBU) approach that facilitates the convergent assembly of multidimensional framework materials using a preassembled anionic SBU {P8W48}, with integrated "pore" 1 nm in diameter, and electrophilic manganese {Mn2+} linkers. This yields two new POMOFS with augmented hexagonal tiling (2 and 3), related to a known three-dimensional (3D) cubic array K18Li6[Mn-8(II)(H2O)(48)P8W48O184].108H(2)O (1), K-12[Mn-14(II)(H2O)(30)P8W48O184].111H(2)O (2), and K8Li4[Mn-1.4(II)(H2O)(26)P(8)W(48)O(18)4].105H(2)O (3). These frameworks have been crystallized from aqueous Li-buffered solutions of {P8W48} and Mn-II(ClO4)(2).6H(2)O via careful control of the synthetic strategy akin to a crystal engineering approach using cation and temperature control to isolate different material architectures shown by compounds 1-3.