[Mn(H2O)2]4[HNC5H 4(COO)]2[C6H2(COO)4] 2·4H2O - A Three-dimensional Coordination Polymer with Guest Water Molecules in Channel-like Voids | [Mn(H2O)2]4[HNC5H 4(COO)]2[C6H2(COO)4] 2·4H2O - Ein dreidimensionales Koordinationspolymer mit Gastwassermolekülen in kanalartigen Hohlräumen