The synthesis, characterization and solid-state luminescence spectroscopy of mononuclear (f), heterodinuclear (d-f) and heterotrinuclear (d-f-d) coordination compounds with the compartmental ligand N,N'-bis(3-hydroxyl salicylidene)benzene-1,2-diamine (H2L) are reported. The trivalent lanthanide ions Nd(III), Sm(III), Eu(III), Gd(III), Tb(III) and Dy(III) as single metal centres or in combination with either Zn(II) or Ni(II) were coordinated. Compounds are characterised by elemental analyses, IR, 1D and 2D solution (1)H and (13)C NMR spectroscopy, measurements of magnetic moments and solid state UV-Vis-NIR reflectance, luminescence and Raman spectroscopy techniques. Crystal structures of the dinuclear compounds [SmZn(O2NO)3(L)(OH2)]·EtOH and [DyZn(O2NO)2(Cl)(L)(EtOH)]·3EtOH and the trinuclear compound [TbZn2(L)2(Cl)2(OH2)](NO3)·EtOH are presented, where samarium(iii) displays a coordination number of ten, with a bicapped cubic geometry, while for the dysprosium compound a nine-coordinated environment with a tricapped trigonal prismatic geometry is shown. Their crystals belong to the triclinic system and the P1[combining macron] space group. The coordination number for terbium(iii) in the trinuclear complex is nine, with a tricapped trigonal prismatic geometry, and its crystal belongs to the monoclinic system, space group C2/c. For these three compounds, the zinc ion stabilises a penta-coordinated environment with square pyramid geometry. All mononuclear and dinuclear compounds are neutral, whereas the trinuclear complexes are ionic. The results of DFT theoretical calculations for the ligand (H2L) are used to assign the ligand singlet and triplet excited state energy levels. Luminescence studies of the neodymium compounds indicate that the ligand is a sensitizer for NIR emitters.

The coordination behavior of the antiulcer drug cimetidine (cime) towards transition metal ions was investigated. The synthesis and characterization of [Cr(cime)₂Cl₂]Cl·3H₂O, [Co(cime)Cl₂]·5H₂O, [Co(cime)₃Cl]Cl·3H₂O, [Ni(cime)Cl₂(H₂O)₂]·H₂O, [Cu(cime)Cl₂]·2H₂O, [Cu(cime)₂Cl(H₂O)]Cl·H₂O, [Cu(cime)₃Cl₂]·3H₂O, [Cu₂(cime)Cl₄], and [Zn(cime)Cl₂]·1.5H₂O are discussed, where cime acts as monodentate (imidazole N3) or bidentate ligand (N3 and S8). IR, UV-vis, EPR and NMR spectroscopies, mass spectrometry (FAB+), were employed for the characterization. In order to identify the most reactive areas of cimetidine, the electrostatic potential map of the ligand was calculated; also the structures of minimum energy of the coordination compounds were modeled using DFT (B3LYP/def2-TZVP) calculations.

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