Systematic exploration of a rutile-type zinc(ii)-phosphonocarboxylate open framework: the factors that influence the structureElectronic supplementary information (ESI) available: Detailed structural information, TG analysis data and PXRD data. CCDC reference numbers 751707, 776920, and 776921-776925. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c0dt00525h

To systematically explore the assembly mechanism of a rutile-type open framework of {[Zn 3 ( pbdc ) 2 ]·2H 3 O} n ( 3 ) (H 4 pbdc = 5-phosphonobenzene-1,3-dicarboxylic acid) constructed by 3-connected pbdc ligands and 6-connected Zn 3 (CO 2 ) 4 (PO 3 ) 2 secondary building units (Zn 3 -SBUs), three major factors including solvothermal procedures, types of solvents and amines, are taken into consideration. Seven novel structures, namely {[Zn 5 ( pbdc ) 2 (OH) 2 (H 2 O) 4 ]·4H 2 O} n ( 1 ), {[Zn 3 ( pbdc ) 2 ·H 2 O]·(H tea )·H 3 O·2-5(H 2 O)} n ( 2 ), {[Zn 3 ( pbdc ) 2 ](H 3 O) 2 ( dma )} n ( 4 ), {[Zn 2 ( pbdc )( taea )]·3H 2 O} n ( 5 ), {[Zn 3 ( pbdc ) 2 (H pda ) 2 ]·2H 2 O} n ( 6 ), {[Zn 5 ( pbdc ) 2 (H pbdc ) 2 ]·2H 2 pz ·9H 2 O} n ( 7 ), {[Zn 3 ( pbdc ) 2 ]·H pd ·H 3 O·4H 2 O} n ( 8 ) are obtained. The results indicate that the layered-solvothermal method and the isopropanol solvent play crucial roles in the construction of the special anionic open framework of [Zn 3 ( pbdc ) 2 ] 2− . Changing these two factors led molecular assembly away from the rutile-type open framework. However, amines play a variable role in the framework, which means that by using appropriate amines, molecular assembly could generate the open framework of [Zn 3 ( pbdc ) 2 ] 2− with pores decorated by amines. These results suggest a different approach towards decorating pores in anionic frameworks with precise structural information. Using appropriate amines, an anionic rutile-type open framework with pores decorated by amines can be produced, offering a different approach to cation-exchange.