10 research outputs found
Dibromidobis(3,5-dimethyl-1H-pyrazole-κN 2)cobalt(II)
In the mononuclear title complex, [CoBr2(C5H8N2)2], the CoII atom is coordinated by two N atoms from two monodentate 3,5-dimethylpyrazole ligands and two Br atoms in a highly distorted tetrahedral geometry. In the crystal, the complex molecules are linked by intermolecular N—H⋯Br hydrogen bonds into chains along [101]. An intramolecular N—H⋯Br hydrogen bond is also present
Diaquabis(pyridine-2-carboxylato-κ2 N,O)manganese(II) dimethylformamide hemisolvate
There are two crystallographically independent complex molecules with very similar geometries in the unit cell of the title compound, [Mn(C6H4NO2)2(H2O)2]·0.5C3H7NO. The central ion is situated in a distorted octahedral environment of two N- and four O-donor atoms from two pyridine-2-carboxylate ligands and two cis-disposed water molecules. The carboxylate ligands are coordinated in a chelate fashion with the formation of two five-membered rings. In the crystal, the complex molecules are connected by O—H⋯O hydrogen bonds between the coordinated water molecules and the uncoordinated carboxylate O atoms, thus forming hydrogen-bonded walls disposed perpendicularly to the bc plane
fac-Tris(pyridine-2-carboxylato-κ2 N,O)cobalt(III)
In the title compound, [Co(C6H4NO2)3], the CoIII ion lies on a threefold rotation axis and is in a distorted octahedral environment defined by three N and three O donor atoms from three fac-disposed pyridine-2-carboxylate ligands. The ligands are coordinated in a chelate fashion, forming three five-membered rings. In the crystal, translationally related complex molecules are organized into columns along [001] via C—H⋯O hydrogen bonds
(3-Acetyl-4-methyl-1H-pyrazol-1-ide-5-carboxylato)bis(1,10-phenanthroline)nickel(II) 3.5-hydrate
The title compound, [Ni(C7H6N2O3)(C12H8N2)2]·3.5H2O, crystallizes as a neutral mononuclear complex with 3.5 solvent water molecules. One of the water molecules lies on an inversion centre, so that its H atoms are disordered over two sites. The coordination environment of NiII has a slightly distorted octahedral geometry, which is formed by one O and five N atoms belonging to the N,O-chelating pyrazol-1-ide-5-carboxylate and two N,N′-chelating phenanthroline molecules. In the crystal, O—H...O, N—H...O and O—H...N hydrogen bonds involving the solvent water molecules and pyrazole-5-carboxylate ligands form layers parallel to the ab plane. These layers are linked further via weak π–π interactions between two adjacent phenanthroline molecules, with centroid-to-centroid distances in the range 3.886 (2)–4.018 (1) Å, together with C—H...π contacts, forming a three-dimensional network
Chronostratigraphy of Jerzmanowician. New data from Koziarnia Cave, Poland
Lincombian-Ranisian-Jerzmanowician (LRJ) industries are extremely scarce in Central Europe. Therefore, each LRJ site is of great importance. One of them is Koziarnia Cave in Poland situated eastwards relative to other LRJ sites. Our investigations of this cave provided new chronostratigraphic data for the LRJ industries. A detail debitage analysis recognised the ventral thinning chips and enabled identification of the LRJ assemblage-containing stratum. Besides the LRJ assemblage, strata with traces of Late Middle Palaeolithic and Early Gravettian occupation were found at the site. The radiocarbon dates of Koziarnia samples show that the archaeological settlement represents one of the oldest Gravettian stays north to the Carpathians. Moreover, these dates demonstrate that humans and cave bears had alternately occupied the cave. Additionally, the radiocarbon dates indicate relatively young chronology of the Jerzmanowician occupation in Koziarnia Cave (ca. 39-36 ky calBP). The results suggest the long chronology of the LRJ technocomplex, exceeding the Campanian Ignimbrite event.Cave siteMiddle/Upper Palaeolithic transition; Leafpoint industries; Lincombian-Ranisian-Jerzmanowician; Early Gravettia