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The influence of counter ion and ligandmethyl substitution on the solid-state structures and photophysical properties of mercury(ii) complexes with (E)-N-(pyridin-2-ylmethylidene)arylamines

“…In contrast, with phen and dmph, monomeric structures with distorted tetrahedral coordination geometries of composition Hg(phen/dmph)I 2 are observed. 45 This is as expected because the presence of bulky phen or dmph ligands inhibits aggregation. However, for Hg(phen) 2 Cl 2 a six-coordinate complex with a distorted octahedral geometry was observed.…”

Bis(1,10-phenanthroline)(thiosulfato)manganese(II) methanol solvate andcatena-poly[[diaqua(2,9-dimethyl-1,10-phenanthroline)manganese(II)]-μ-thiosulfato]

“…In recent years, a large amount of structural work on the complexing properties of the thiosulfate ion has been published (Brezeanu et al, 1998;Carter & Drew, 1999;Freire et al, 1999Freire et al, , 2001Freire, Baggio, Baggio & Mariezcurrena, 2000;Freire, Baggio, Suescun & Baggio, 2000). From these results, it is clear that the anion behaves as a very versatile ligand in coordination compounds involving transition metals, displaying an internal geometry very dependent on the type of coordination present.…”

“…Therefore, it is of interest to explore the bonding character-istics of other Mn±thiosulfate compounds in the light of this rather unpredictable behavior. In addition, our experience with the thiosulfate anion complexed to a variety of different metal centers suggests that substantially different structures can be obtained through the introduction of small differences in the coordinating organic ligands used or even by using the same ligands but working under slightly different ambient conditions (Freire et al, 1999;Freire, Baggio, Baggio & Mariezcurrena, 2000;Freire, Baggio, Suescun & Baggio, 2000).…”

Bis(1,10-phenanthroline-N,N′)(thiosulfato-O,S)nickel(II)–water–methanol (1/0.92/1.4) and bis(2,2′-bipyridyl-N,N′)(thiosulfato-O,S)nickel(II)–water–methanol (1/2/0.55)

“…Recently, two crystal structures of nickel thiosulfate complexes have been reported, namely triaqua(2,2 H -bipyridyl-N,N H )(thiosulfato-S)nickel(II) dihydrate and triaqua(1,10phenanthroline-N,N H )(thiosulfato-S)nickel(II) monohydrate (Freire et al, 1999), in which the anion binds to the cation in a monodentate mode through sulfur. In this case, only slight distortions are observed in the anion geometry.…”

“…This ®tting worsens dramatically when the solvent molecules are also considered, and this reveals why the structure does not really crystallize in a more symmetric space group (monoclinic with a single molecule per asymmetric unit); the included solvent molecules do not exist in pairs related by the pseudocenter of symmetry. As a result of the pseudosymmetry, both Ni ions have almost identical environments, with the four NiÐN distances [2.060 (5)±2.095 (6) A Ê ] being normal for a hexacoordinated nickel cation, and only slightly longer than those observed in S-bonded nickel thiosulfates (2.041± 2.070 A Ê ; Freire et al, 1999). The S,O-chelating thiosulfate completes the coordination sphere, in a similar way to that of the thiourea complex of Gasparri et al (1969).…”