Reactions of p-toluenesulfohydrazide with R-isothiocyanates afford new ligands containing both the sulfonamide and thiosemicarbazide moieties (L R : R= cyclohexyl (Cy) or phenyl (Ph)). L R reacts with AgNO 3 in EtOH in a 2:1 M ratio leading to formation of colourless Ag(I) complexes of general formula [Ag(L R ) 2 ]NO 3 . The crystal structure of a representative complex was determined by crystallographic studies and shows the Ag(I) coordinated by two thiosemicarbazide ligands in a Smonodentate coordination mode along with a significant interaction with a nitrate counter-ion in a bent geometry.Photophysical studies show that both the free ligands and complexes are essentially non-luminescent at room temperature. At 77 K and glassy media, the silver complexes exhibit a luminescence band in the visible-light region. Besides, experimental and theoretical analyses suggest the population of the triplet state of these complexes after electronic excitation at around 250 nm. Overall, it was verified that the observed emission of the Ag(I) complexes can be attributed to 3 MLCT radiative decay and that the silver complex with L Ph shows a higher intensity emission than the complex with L Cy .

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The binuclear oxidovanadium(V) complex [{VO(L)}2(μ-O)(μ-H2O)]∙2CH3CN (1), where L2– is the dianion of the Schiff base 2-salicylaldehyde-2-hydroxybenzoylhydrazone, were prepared and characterized by elemental analysis, FTIR, 1H, 13C and 51V NMR. Furthermore, the crystal structure of the compound 1 was determined by single crystal X-ray diffractometry revealing a distorted octahedral O5N-coordination geometry around the V(V) acceptor centers. The vanadium ions are connected by the μ-O2– and the μ-H2O asymmetric bridges located in the edge between the two octahedrons which keeps a distance of 3.194 Å between the two vanadium centers. Crystal data for C32H28N6O10V2 (M =758.48 g/mol): orthorhombic, space group P212121 (no. 19), a = 12.9655(8) Å, b = 14.1902(9) Å, c = 18.4379(10) Å, V = 3392.3(4) Å3, Z = 4, T = 293(2) K, μ(MoKα) = 0.616 mm-1, Dcalc = 1.485 g/cm3, 18803 reflections measured (3.622° ≤ 2Θ ≤ 56.704°), 8263 unique (Rint = 0.0473, Rsigma = 0.1020) which were used in all calculations. The final R1 was 0.0509 (I > 2σ(I)) and wR2 was 0.1531 (all data). The (VO)2(μ-O)(μ-H2O) core in compound 1 represents a rare case and few examples of similar type have been structurally characterized.