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Multi-walled carbon nanotubes (MWCNTs) can self-assemble as cylindrical bundles in some solvents after polystyrene (PS) grafting. In these three-dimensional regular structures, the tubes are oriented and parallel arranged. Every self-assembly structure has an order head and a comparatively loose tail. In order to find out the role that solvent plays, MWCNTs were dispersed in several organic solvents before and after modification. Based on macroscopic stability of suspensions and microscopic state of nanotubes, compatibility between solvents and MWCNTs can be confirmed. According to compatibility difference between tubes and PS, five chosen solvents are divided into three groups: selective solvent, good solvent, and bad solvent. MWCNT-g-PS can self-assemble only in selective solvents. Tetrahydrofuran and benzene are well compatible with PS, but bad with MWCNTs. Driven by the solvent-philic/solvent-phobic interaction, MWCNT-g-PS self-organized regularly as bundles. Because each part of the MWCNT-g-PS is compatible well with 1,2-dichlorobenzene, gathering tendency of the modified tubes have been enervated by their good compatibility and weak amphiphilicity. Grafted or not, nanotubes reveal poor compatibility with methanol and ethanol. Strong incompatibility and limited amphiphilicity make MWCNT-g-PS agglomerate as quickly and irregularly as raw tubes. An adapted hydrophilic/lipophilic balance system is introduced to qualify compatibility and amphiphilicity of MWCNT-g-PS in each solvent. This novel model not only reveals the relationship between solvent and microscopic state of unmodified/modified tubes, but also signifies the decisive role of solvent in self-assembly behaviors of MWCNT-g-PS. [ABSTRACT FROM AUTHOR]

1,2,5-thiadiazole-3,4-dicarboxylic acid (H tdzdc) ligand has been used to construct three coordination compounds [Mg(tdzdc)(HO)]( 1), [Ca(tdzdc)(HO)]( 2) and [Sr(tdzdc)(HO)]( 3) by the solvothermal reaction. Single-crystal structure analyses reveal a mononuclear coordination structure for compound 1 and two dimensional coordination structure both for compound 2 and 3. Furthermore, all of these three compounds comprise any amount of hydrogen bond interactions, which extends their crystal structure into three dimensional (3D) frameworks. Different crystal structure of compounds 1- 3 reveals diversified coordination modes of H tdzdc ligand toward alkaline earth metal ions, depending mainly on the radius and the electron shell number of metal ions used. Graphical Abstract: Based on 1,2,5-thiadiazole-3,4-dicarboxylic acid (H tdzdc) ligand, three new alkaline earth metal compound were synthesized with different structure.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]