| As a large number of molecular knowledge grows,modern chemists have realized that the properties and functionalities of materials not only depend on the properties and functionalities of each molecule,but also rely on the arrangement and aggregation states of the molecules beyond the molecular scale.The subject of supra-molecules focuses on the weak interactions,such as hydrogen bonding,Ï€-Ï€stacking,anion-Ï€interaction,van der Waals and so on,and on how these interactions lead to the aggregation of countless molecules and the formation of the supramolecules.The cooperation of these weak interactions among molecules can produce strong intermolecular forces along certain direction,which are effectively for building the supramolecular structure.Studying and understanding the nature and rule of these weak interactions are significant for the designation and fabrication of new functional materials in the diverse areas of chemistry,biology,material science,and informatics and so on.In this thesis,ten complexes between metal ion-organic ligand were successfully prepared in our lab and the effects of hydrogen bonding and aromatic stacking on the structures of the complexes were investigated.The ten novel compounds(â… )～(â…©) were formed among the transitional metal ions of Mn(â…¡),Ni(â…¡),Co(â…¡),Cu(â…¡) and Zn(â…¡),theneutral organic ligands of imidazole,3-Hydroxypyridinium and 1,10-phenanthlorine,and the anionic ligands of 1,4-naphthalenedicarboxylic acid(1,4-NDCA),4-Chloro-2-hydroxybenzoic acid, 3,4-Dichlorobenzoic acid and 3-nitrobenzoic acid.They are:[Mn(C3H4N2)6] [Mn(C3H4N2)3(H2O)3](C12H6O4)2(â… ),[Ni(C3H4N2)6][Ni(C3H4N2)3(H2O)3] (C12H6O4)2(â…¡),[Co(C3H4N2)6][Co(C3H4N2)3(H2O)3](C12H6O4)2(â…¢),{[Cu(C12H6O4) (C3H4N2)2(H2O)2H2O]}n(â…£),Cu(C7H4O3Cl)2(C5H5NO)2(â…¤),Zn(C7H4NO4)2 (C5H5NO)2(â…¥),Co(C7H3O2Cl2)2(C5H5NO)2(H2O)2(â…¦),Mn(C7H3O2Cl2)2(C5H5NO)2 (H2O)2(â…§).{Cu(C7H3O3Cl)(C12H8N2)(H2O)}2(â…¨),2C5H6NO2+·C4H2O42-(â…©), respectively.Among these compounds,neutral ligands and anion ligands both contain many hydrogen biding sites.Additionally,the neutral and anionic ligands also have aromatic rings so that the aromatic stacking may be formed in the compounds. Furthermore,the carboxyl end group of anionic ligands will lead to the diversity of coordination.The structures of these compounds were determined by single crystalâ…©-Ray diffraction.Useful information about each ligand and the weak interactions like aromatic stacking,hydrogen bonding and their supramolecular structure were thus obtained.For the compounds(â… ),(â…¡) and(â…¢),the crystal structures and cell parameters are much at the same and the space groups are identical.Therefore,the compounds (â… ),(â…¡) and(â…¢) are isomorphism.It is similar for compounds(â…¦) and(â…§).It is thus concluded that the metal ions did not affect the supra-molecular structure of (â… ),(â…¡) and(â…¢).By studying the behavior of different substituted benzoate ligands involved in the aromatic stacking,we found that the aromatic stacking existed between 3, 4-Dichlorobenzoic acid ligands in(â…¦) and(â…§),the same with 4-chloro-2-hydroxybenzoic acid and phen in(â…¨).There was noÏ€-Ï€stacking between other anionic ligands.Among all the neutral ligands,weakÏ€-Ï€stacking was only observed for the 3-hydroxypyridine in(â…¥),in which the distance between the two phen rings is about 3.594(?).Many reference documents shows the benzoic acid can't formÏ€-Ï€stacking in complexes,we can draw the conclusion that dichlorobenzoic acid can form theÏ€-Ï€stacking easily and the stongth ofÏ€-Ï€stacking depends on the number of substituted chlorine.From the experimental results of the ten compounds,it is found that C—H...Ï€interactions and hydrogen bonding exist wildly in the compounds.These interactions together withπ—πstacking play important roles in stabilizing the supermolecular structures of the compounds.
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