The synthesis, structures and properties of five Cd(II) coordination networks: [Cd(bpdc5, are reported. Complexes 1 and 2 show the pcu and fsd topologies with 2-and 3-fold interpenetrating modes, respectively, and complex 4 exhibits a 2-fold 2D A 2D parallel interpenetration network containing a rotaxane-like motif. Complex 3 is a 1D A 2D polycatenane derived from the helical channels, and the 2D layers are further mutually interdigitated, whereas complex 5 is a 2D A 3D polycatenane based on the undulating sql sheets. These five complexes show different thermal and luminescent properties and the CO 2 capture is preferable to N 2 in the gas sorption for the desolvated product of 1.

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By using isomeric N,N′-di(2-pyridyl)adipoamide (L 1 ), N,N′-di(3-pyridyl)adipoamide (L 2 ) and N,N′-di(4-pyridyl)adipoamide (L 3 ) and isomeric 1,2-benzenedicarboxylic acid (1,2-H 2 BDC), 1,3-benzenedicarboxylic acid (1,3-H 2 BDC) and 1,4-benzenedicarboxylic acid (1,4-H 2 BDC), eight Zn(II) and Cd(II, have been synthesized under hydrothermal conditions. Complexes 1, 4, and 5 form 1D double-looped chain, 1D chain with loops and 2D layer with loops, respectively, and complex 6 exhibits a 1D ladder chain. Complex 2 shows rare 3-fold interpenetrated hcb layers, in which each layer interdigitates with other four parallel layers by directing the 1,3-BDC ligands into the windows of the adjacent nets, whereas complexes 3 and 8 forms planar and undulated hcb layers, respectively. Complex 7 shows a 3D selfpenetrating net of {4 24 .5.6 3 }-ilc topology with a unique arrangement for the L 2 spacer ligands. The L 1 ligands in complexes 3 and 8 adopt the new tetradentate bonding mode involving chelation and bridge through two pyridyl nitrogen atoms and two amide oxygen atoms, whereas the L 2 and L 3 ligands in other complexes show the bidentate bonding mode through the two pyridyl nitrogen atoms. The various bonding modes and the ligand-isomerism of the spacer ligands BDC 2− and L 1 −L 3 as well as the identity of the metal center play important roles in determining the structural diversity.

Structure-directing roles of auxiliary polycarboxylate ligands in the formation of Zn(II) and Cd(II) coordination polymers based on a flexible N,N9-di(3pyridyl)dodecanediamide3

In this paper', the methodology of generating an optimal trajectory on a complex terrain for a specific vehicle is proposed. The possible paths are constrained by the Limitations on the terrain and the capability of the vehicle. To deal with these constraints, the notions of forbidden paint, forbidden direction, and forbidden path are introduced. After certain constants are specified, the method of dynamic programming is then invoked to find the optimal solution. If the target is beyond the maximal range of the vehicle, appropriate senice stations are selected by using the auction algorithm To speed up the computation process, the ideas of bi-spiral scheme and instant update are employed. With all the techniques at hand, numerical results show that the proposed method can generate the desired bajectory eiTiciently.