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One new lead(II) coordination supramolecular complex (CSC) (1D), [Pb2(L)2(I)4]n, L = C4H6N2 (1-methyl imidazole), has been synthesized under different experimental conditions. Micrometric crystals (bulk) or nano-sized materials have been obtained depending on using the branch tube method or sonochemical irradiation. All materials have been characterized by scanning electron microscopy (SEM), powder X-ray diffraction (PXRD) and FT-IR spectroscopy. Single crystal X-ray analyses on complex 1 showed that Pb2+ ion is 4-coordinated. Topological analysis shows that the complex 1 is 2,3,5C2 net. Finally, the role of reaction time and temperature on the growth and final morphology of the structures obtained by sonochemical irradiation have been studied.

Two new lead(II) coordination polymer complexes (CSCs) (2D), [Pb2(L)2(Br)2]n·H2O (1), [Pb2(HL/)(L/)(H2O)2]n·H2O (2), where L = C6H5NO2 (2-pyridinecarboxylic acid) and L/ = C9H6O6 (1,3,5-tricarboxylic acid), have been synthesized under different experimental conditions. Micrometric crystals (bulk) or microsized materials have been obtained depending on using the branch tube method or sonochemical irradiation. All materials have been characterized by scanning electron microscopy (SEM), powder X-ray diffraction (PXRD) and FT-IR spectroscopy. Single crystal X-ray analyses on complexes 1 and 2 shows that Pb2+ ions are 8-coordinated, 7 and 9-coordinated, respectively. Topological analysis shows that the compound 1 and 2 are 4,6L26 and bnn net, respectively. However, neither the shape nor the morphology is maintained, showing the role of sonochemistry to modulate both morphology and dimensions of the resulting crystalline material, independently of whether we have a 2D coordination polymer (CP). Finally, micro structuration of lead(II) bromide oxide and lead(II) oxide have been prepared by calcination of two different lead (II) CPs at 700 °C that were characterized by SEM and XRD.

Reaction between N,N-dimethylebiguanidine, Met = Metformin, and 4-hydroxy-2,6-pyridinedicarboxylic acid, HO-dipicH2, results in the formation of a novel proton transfer compound, [MetH2][HO-dipicH]2·H2O, 1. The characterization was performed using FTIR, UV–Vis, 1H and 13C NMR spectroscopy and X-ray crystallography. The crystal system is triclinic with space group P1 and two molecules per unit cell. The protonation constants of O-dipic and Met, in all of probability protonated forms, and the equilibrium constants for the O-dipic–Met proton transfer system were investigated by the potentiometric pH titration method using the Hyperquad2008 program. The stoichiometry of the proton transfer species in solution were in agreement with the solid state result.

Two new mercury(II) coordination supramolecular compounds (CSCs) (1D and 0D), [Hg(L)(I)] (1) and [Hg(L′)(SCN)]·2HO (2) (L = 2-amino-4-methylpyridine and L′ = 2,6-pyridinedicarboxlic acid), have been synthesized under different experimental conditions. Micrometric crystals (bulk) or nano-sized materials have been obtained depending on using the branch tube method or sonochemical irradiation. All materials have been characterized by field emission scanning electron microscope (FESEM), scanning electron microscopy (SEM), powder X-ray diffraction (PXRD) and FT-IR spectroscopy. Single crystal X-ray analyses on compounds 1 and 2 show that Hg ions are 4-coordinated and 5-coordinated, respectively. Topological analysis shows that the compound 1 and 2 have 2C1, sql net. The thermal stability of compounds 1 and 2 in bulk and nano-size has been studied by thermal gravimetric (TG), differential thermal analyses (DTA) for 1 and differential scanning calorimetry (DSC) for 2, respectively. Also, by changing counter ions were obtained various structures 1 and 2 (1D and 0D, respectively). The role of different parameters like power of ultrasound irradiation, reaction time and temperature on the growth and morphology of the nano-structures are studied. Results suggest that increasing power ultrasound irradiation and temperature together with reducing reaction time and concentration of initial reagents leads to a decrease in particle size.

Nanoparticles of two new coordination compounds, [Hg2(L)2(Br)4]n (1) and [Hg(L′)(SCN)2] (2), (L = 2-amino-4-methylpyridine, L′ = 2,6-pyridinedicarboxlic acid), have been synthesized by use of a sonochemical process and characterized by scanning electron microscopy (SEM), field emission scanning electron microscopy(FESEM), X-ray powder diffraction (XRPD), Fourier transform infrared spectroscopy (FTIR) spectroscopy and elemental analyses. The single crystal X-ray data of compounds 1 and 2 imply that the Hg(II) ions are four and five coordinated, respectively. Topological analysis shows that 1D and 0D coordination networks of 1 and 2 can be classified as underlying nets of topological types 2C1 and 1,3M4-1, respectively. The thermal stability of compounds has been studied by thermal gravimetric (TG) and differential thermal analyses (DTA). The role of temperature, reaction time and ultrasound irradiation power on the size and morphology of “nano-structures” 1 and 2, has been investigated. Results claim that an increase of temperature, sonication power and decrease in reaction time leads to a decrease of particle size.

Compound DAPH+Cl−·3H2O (1), and complexes Mn(dipic)(H2O)3 (2) and [DAPH][Zn(dipicH)(dipic)]·4H2O (3), (dipicH2 = 2,6-pyridinedicarboxylic acid and DAP = 2,3-diaminophenazine) were prepared from the reaction of MgCl2·4H2O and ZnCl2 with mixture of o-phenylenediamine (OPD) and 2,6-pyridinedicarboxylic acid in water. These compounds were characterized by elemental analysis, FTIR, 1H NMR and UV–Vis spectroscopy. The solid-state structure of [DAPH][Zn(dipicH)(dipic)]·4H2O (monoclinic, P21/c) was determined by the single crystal X-ray diffraction method. The protonation constants of dipic and DAP, in all of probability protonated forms, the equilibrium constants for the dipic–DAP proton transfer system and the stoichiometry and stability constants of binary and ternary complexes of this system with Zn2+ and Mn2+ ions in aqueous solution were investigated by the potentiometric pH titration method. The stoichiometries of the most complex species in solution were compared with corresponding crystalline complexes in the solid state.