A Novel POM-Based Inorganic Porous Framework: Synthesis, Structure and Properties. -(H2en)[Mn3P4Mo4O28] is hydrothermally synthesized from a mixture of (NH4)6Mo7O24, Mn(OAc)2, Dy(OAc)3, en, H3PO4, and H2O (pH 5, autoclave, 180°C, 5 d; 75% yield). The compound crystallizes in the tetragonal space group I41/a with Z = 4 (single crystal XRD). PO4 groups link Mn atoms to form three-fold interpenetrated adamantane-like networks. Mo-O helical chains are connected with the adamantane network through μ2-bridging oxygen atoms and PO4 groups. PO4, MnO4, MnO6, and MoO6 polyhedra form a three-dimensional framework with one-dimensional channels that host the diprotonated ethylenediamine molecules. The compound shows antiferromagnetic coupling, good thermal stability, and active electrochemical behavior. -(SUN, Y.; LU*, J.; LI, D.; DOU, J.; Inorg. Chem. Commun. 36 (2013) 166-169, http://dx.