Formation of entangled Co(ii) coordination polymers based on bis-pyridyl-bis-amide and angular dicarboxylate ligands: a structural comparison

Abstract

Co(ii) coordination polymers containing bis-pyridyl-bis-amide ligands with flexible spacers that result in long N---N distances are more probable to form entangled networks than those with rigid-bulky ones.

Cu(II) Coordination Polymers Containing Mixed Ligands with Different Flexibilities: Structural Diversity and Iodine Adsorption

“…The Cu(II) cations are linked together by 1,3,5-HBTB 2− and L 2 ligands to afford a 3D structure. If the dinuclear Cu(II) units are defined as six-connected nodes, the structure can be simplified as a six-connected net with (4 12 •6 3 )-pcu topology, Figure 5b. The 3D nets penetrate into the neighbors to form a threefold 3D interpenetration structure, Figure 5c, demonstrating that the combination of the flexible L 2 and 1,3,5-HBTB 2− may lead to the formation of the entangled CP [12].…”

“…The ability of the CPs to adapt iodine molecules to the voids of the network structures may govern the iodine adsorption capacity [16][17][18][19]. The solvent accessible volumes calculated by using the PLATON program [20] for 1-6 were 1.5, 17.3, 34.4, 2.9, 11.8 and 10.4%, respectively, of the unit cell volume, indicating that complex 3, which displays the three-fold interpenetrated 3D net with (4 12 •6 3 )-pcu topology, may accommodate more iodine than the other complexes. However, the best adsorption factor of 290.0 mg g −1 at 60 • C for 360 min was observed for 5, demonstrating the important role of the flexibility of the neutral spacer ligands, L 1 , L 2 and L 3 , in determining the iodine adsorption capacities of 1-6.…”

Structural diversity of cadmium coordination polymers based on an extended anilate-type ligand

“…Combining these properties of the cadmium ion allows us to expect a variety of possible structures when forming coordinating polymers. As shown in recent works, 71–76 another important point that will contribute to obtaining different topologies in the final product is the rigidity/flexibility of the N-donor linkers. Together with the possibility of Z / E isomerization in the diiminophenylene moiety of the extended anilate ligand H 2 L , this will allow to adapt the conformations of the organic bridges to the construction of a coordination sphere suitable for a particular metal cation.…”