Assembly of Dipicolinic Acid by Alkali-Metal Cations

Different types of structures of hydrogen-bond assemblies derived from partially deprotonated dipicolinic acid (LH2) molecules having alkali metal cation such as sodium, potassium and cesium are structurally characterised. These self assembled complexes have general formula [M(LH)(LH2)(H2O) (m) ] (n) xH(2)O {m = 2, 3, n = 1, 2, n, and x = 0, 0.5 M = Na (1); K (2) and Cs(3)}. Sodium complex is a hepta-coordinate mononuclear complex; potassium complex is octa-coordinate complex with dinuclear K2O2 type of carboxylate core; whereas the cesium complex is nona-coordinate polymeric complex. All these complexes crystallises in Triclinic, P-1 space group. Sodium complex has a = 6.9003(4) ; b = 11.1440(6); c = 11.2059(5); alpha = 85.695(4)A(0); beta A = 82.103(3)A(0); gamma A = 87.432(4)A(0) and volume = 850.60(8) (3) Z = 2; Potassium complex has a = 7.0937(4); b = 11.0034(5); c = 11.2732(6); alpha = 91.603(3)A(0); beta A = 96.088(3)A(0); gamma A = 97.207(4)A(0); volume = 867.29(8) (3); Z = 1 and cesium complex has a = 7.1410(6); b = 11.0625(8); c = 12.0667(9); alpha = 96.849(4)A(0); beta A = 93.850(4)A(0); gamma A = 105.495(4)A(0); volume = 907.14(12) (3); Z = 2.