Crystal structure of a polymeric complex of lead(II) with 2,6-dihydroxybenzoic acid

Novel luminescent materials based on silica doped with an europium(III) complex of 2,6-dihydroxybenzoic acid

“…The crystal structures of transition-metal complexes of dihydroxybenzoic acids (2, (2, 4 ]·3H 2 O [11], [Cu(2,6-Hdhb) 2 (2, 3 (H 2 O) 4 ]·2H 2 O [14]. In these complexes, 2,3-H 2 dhb act as a catecholato type chelate, whereas 2,6-H 2 dhb shows a more versatile coordination mode (either using both the carboxylate group and an adjacent hydroxyl group in a salicylato type chelate, or the carboxylate group in a monodentate or bidentate fashion).…”

Ionothermal synthesis, structure and optical properties of three new organic–inorganic hybrid imidazolium bromoplumbate complexes

“…The coordination geometry of the [PbO n ] polyhedra in Pb(II) compounds is hemidirected for low coordination numbers (2-5) and holodirected for high coordination numbers (9 and 10). For intermediate coordination numbers (6-8) either type of stereochemistry is found [29,[35][36][37]. In compounds 1-3, if slightly long Pb-Br distances (3.2412(24) Å in 1, 3.3804(20) Å in 2, and 3.3612(18) Å in 3) are taken into account, the hemidirected [PbBr 5 ] sphere will be changed to holodirected [PbBr 6 ] sphere.…”

“…The Pb centers are separated by 3.9883(10) (1), 3.9945(21) (2) and 4.0006 (16) (3) Å, respectively. It should be noted that the stereochemical activity of lone-pair electrons in the Pb 2+ cation plays a role in the coordination geometry [29,[35][36][37]. The coordination geometry of the [PbO n ] polyhedra in Pb(II) compounds is hemidirected for low coordination numbers (2-5) and holodirected for high coordination numbers (9 and 10).…”

Coordination complexes of iron(III) with 3-hydroxy-2(1H)-pyridinone, 2,3-dihydroxybenzoic acid and 3,4-dihydroxybenzoic acid: preparation and characterization in the solid state

“…In the spectrum of (6), a medium and broad absorption (3520-3280 cm-a) indicates that lattice H20 is present (53 Bands at ca. 3200 cm-1 in (2) and (4) (replaced, after dehydration, by a series of multiple absorptions in the range 3100-2900 cm-1) are attributed to v(OH)phenolic (14). Absorptions ascribed to 6(OH)_he.oli c are detected at ca.…”