The title salt, [Co(C10H7NOS)2(H2O)2](BF4)2, crystallizes in the monoclinic system (space group P21/n). In the complex cation, the central CoII atom (site symmetry 1) has a pseudo-octa­hedral coordination environment with bonding to pyridyl N [2.0189 (13) Å] and carbonyl O [2.0869 (11) Å] atoms from the 2-thienyl 2-pyridyl ketone ligands. The remaining bonds are to water mol­ecules [2.0903 (13) Å], which form a hydrogen-bonded extended structure with BF4− counter-ions. The thienyl ring shows disorder through an approximate twofold rotation with an occupancy ratio of 0.951 (3):0.049 (3).

The complex title salt, [Ni(C10H7NOS)2(H2O)2](BF4)2, has monoclinic symmetry (space group P21/c) with the central NiII atom located at an inversion center. The coordination environment around the NiII atom is pseudo-octa-hedral with bonding to pyridyl N [2.0342 (6) Å] and carbonyl O [2.0402 (5) Å] atoms from two chelating 2-thienyl 2-pyridyl ketone ligands. The remaining bonds are to water mol-ecules [2.0989 (7) Å], which are hydrogen-bonded to BF4 - counter-ions. The crystal structure was refined using nonspherical scattering factors.

The title salt, [Co(C10H7NOS)2(H2O)2](BF4)2, crystallizes in the monoclinic system (space group P21/n). In the complex cation, the central CoII atom (site symmetry 1) has a pseudo-octa-hedral coordination environment with bonding to pyridyl N [2.0189 (13) Å] and carbonyl O [2.0869 (11) Å] atoms from the 2-thienyl 2-pyridyl ketone ligands. The remaining bonds are to water mol-ecules [2.0903 (13) Å], which form a hydrogen-bonded extended structure with BF4 - counter-ions. The thienyl ring shows disorder through an approximate twofold rotation with an occupancy ratio of 0.951 (3):0.049 (3).

The title salt, [Co(C10H7NOS)2(H2O)2](BF4)2, crystallizes in the monoclinic system (space group P21/n). In the complex cation, the central CoII atom (site symmetry 1) has a pseudo-octahedral coordination environment with bonding to pyridyl N [2.0189 (13) Å] and carbonyl O [2.0869 (11) Å] atoms from the 2-thienyl 2-pyridyl ketone ligands. The remaining bonds are to water molecules [2.0903 (13) Å], which form a hydrogen-bonded extended structure with BF4− counter-ions. The thienyl ring shows disorder through an approximate twofold rotation with an occupancy ratio of 0.951 (3):0.049 (3).

The structure of the title complex, [Zn2(C2H3O2)4(C11H9N3O)2], is triclinic containing half of the molecule in the asymmetric unit. Each zinc atom is coordinated to a pyridyl and oxime nitrogen from one di-2-pyridyl ketone oxime (dpko) ligand and a third nitrogen from the other dpko pyridyl ring. Additionally, each zinc is coordinated to two acetato anions, one of which is bidentate and the other monodentate. The uncoordinated oxygen of the monodentate acetato group is involved in a hydrogen bond with the oxime hydrogen. The packing in the crystal is assisted by weak C—H...O interactions between acetato groups and neighboring pyridyl rings.

The crystal structure of the title compound, [Ni(C13H11N2O2)(H2O)4]Br3·2H2O, contains an octahedral NiII atom coordinated to the enol form of 1,3-dipyridylpropane-1,3-dione (dppo) and four water molecules. Both pyridyl rings on the ligand are protonated, forming pyridinium rings and creating an overall ligand charge of +1. The protonated nitrogen-containing rings are involved in hydrogen-bonding interactions with neighoring bromide anions. There are many additional hydrogen-bonding interactions involving coordinated water molecules on the NiII atom, bromide anions and hydration water molecules.

The title compound, C 18 H 20 N 4 O 4 , was synthesized via the base-assisted reaction of piperazine and 2-nitrobenyl bromide in toluene: the complete molecule is generated by a crystallographic inversion centre in the solid state.

The structure of tetraaqua[2,6-diacetylpyridine bis(semicarbazone)]samarium(III) trinitrate, [Sm(C11H15N7O2)(H2O)4](NO3)3, has monoclinic (P21/c) symmetry. The 2,6-diacetylpyridine (DAPSC) ligand is pentadentate. The coordination of the DAPSC ligand and four coordinated water molecules around the metal cation is best described as a distorted tricapped trigonal prism. The structure displays intermolecular hydrogen bonding. The structure is isomorphous with many other published lanthanide(III) nitrate salts with the DAPSC ligand, 2,6-diacetylpyridinebis(semicarbazone). One of the three nitrate counter-anions is disordered, which is consistent with the structures of other +3 lanthanide nitrate salts with DAPSC. Refinement of occupancies for the disordered nitrate group gave major and minor occupancies of 54.9 (14) and 45.1 (14)%, respectively.

The heteroyclic ligand di-2-pyridyl ketone oxime (dpko) was reacted with MBr2·xH2O (M = Cu, Zn), affording several novel complexes. [Cu2(dpko)2Br4][CuBr4] and Zn(dpko)Br2 complexes are analogs of previously reported chloride complexes, and both are structurally and spectroscopically similar to the chloride analogs, [Cu2(dpko)2Cl4]Cl2 and Zn(dpko)Cl2; however, [Cu2(dpko)2Br4][CuBr4] crystallizes as the [CuBr4]2 − salt, while Zn(dpko)X2 exhibits a previously unreported disorder at the oxime site, which we now believe to also found to be present in the Zn(dpko)Cl2 analog. We also present EPR data for both [Cu2(dpko)2Br4][CuBr4] and [Cu2(dpko)2Cl4]Cl2.

The crystal structure of the title compound, [YbCl2(H2O)6]Cl, was determined at 110 K. Samples were obtained from evaporated acetonitrile solutions containing the title compound, which consists of a [YbCl2(H2O)6]+ cation and a Cl− anion. The cations in the title compound sit on a twofold axis and form O—H...Cl hydrogen bonds with the nearby Cl− anion. The coordination geometry around the metal centre forms a distorted square antiprism. The ytterbium complex is isotypic with the europium complex [Tambrornino et al. (2014). Acta Cryst. E70, i27].

The valence region electronic structure of Ln(acac)3 complexes (Ln = Nd, Tm, Pr; acac = acetylacetonate) is investigated using, principally, gas-phase ultraviolet photoelectron (PE) spectroscopy. Analysis of PE spectra focuses on the 7–12 eV region containing the first several ionization bands which likely contain metal f-ionizations and acac-based ionizations. These correspond to oxygen 2p-type orbitals and carbon 2p-type orbitals, which are equivalent to oxygen lone pairs and electrons from the pi-bond system of the ligand.