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The photoluminescence spectra of the known complexes, Sm(L)2(NO3)3 (I, II), Sm(L)(iso-Bu2PS2)3 (III, IV), Sm(L)(iso-Bu2PS2)2(NO3) (V, VI) (L = Phen, 2,2′-Bipy), and Sm(Phen)(C4H8NCS2)3 (VIII), and new compounds, Sm(Phen)((iso-PrO)2PS2)3 (VII), Sm(2,2′-Bipy)(C4H8NCS2)3 · 0.5CH2Cl2 (IX), are obtained and interpreted. Using the X-ray structure analysis data, the crystal structure of the [Sm(2,2′-Bipy)2(NO3)3] complex (II) is determined. Structure II consists of discrete mononuclear molecules having a ten-vertex coordination polyhedron N4O6. The ligands 2,2′-Bipy and NO 3 − are bidentate-cyclic. The influence of the composition of the complexes on the photoluminescence (PL) intensity in the series I–VI is considered. The dependence of the intensity of the band with λmax = 647 nm in the PL spectra of complexes III, VII, and VIII on the type of the sulfur-containing ligand in their composition is established. The band intensity changes in the series VIII > III > VII.

Compounds p-HOOCC6F4COOH · H2O (H2L · H2O), [Tb2(H2O)4(L)3 · 2H2O] n (I), and Tb2(Phen)2(L)3 · 2H2O (II) are synthesized. According to the X-ray structure analysis data, the crystal structure of H2L · H2O is built of centrosymmetric molecules H2L and molecules of water of crystallization. The crystal structure of compound I is built of layers of coordination 2D polymer [Tb2(H2O)4(L)3] n and molecules of water of crystallization. The ligands are the L2− anions performing both the tetradentate bridging and pentadentate bridging-chelating functions. The coordination polyhedron TbO9 is a distorted three-capped trigonal prism. Acid H2L manifests photoluminescence in the UV region (λmax = 368 nm). Compounds I and II have the green luminescence characteristic of the Tb3+ ions, and the band with λmax = 545 nm (transition 5 D 4→ 7 F 5) is maximum in intensity. The photoluminescence intensity of compound II is higher than that for compound I.

Heteroligand complexes Ln(L)(iso-Bu2PS2)2(NO3) (Ln = Sm, Tb, Dy; L = Phen, 2,2′-Bipy) (I–VI) are synthesized. The structure of Dy(Phen)(iso-Bu2PS2)2(NO3) (III) is determined from the data of X-ray structure analysis. The crystal structure of complex III is based on discrete mononuclear molecules in which the Dy atom has distorted dodecahedral coordination (polyhedron N2O2S4). The ligands Phen, iso-Bu2PS 2 − and NO 3 − are bidentate-cyclic. According to the X-ray diffraction analysis data, complexes I and II are isostructural to compound III. Complexes I–VI have photoluminescence in the visible spectral range. The photoluminescence spectra of solid samples of compounds I–VI exhibit bands corresponding to the radiative electron transitions of the Sm3+, Tb3+, and Dy3+ ions. Among the studied compounds I–VI, the Tb(III) complexes are characterized by the most intense photoluminescence.

Chiral sodium salts of N-derivatives of aminoacetic acid based on (+)-3-carene (HLNa) and (−)-α-pinene (HLNa) were synthesized. Complexes Zn(HL)Cl (1), Cd(HL)Cl·0.5H2O (3), Zn(HL′)Cl·0.5H2O (4), and Cd(HL′)Cl·0.5H2O (5) were obtained. The single crystals of the coordination polymer [Zn(HL)Cl·2H2O]n (2) were grown. According to the X-ray diffraction analysis, the crystal structure of 2 consists of 1D chains built of Zn(HL)Cl and water molecules. The coordination polyhedron ClN2O2 is a distorted square pyramid. The HL− ligand performs the chelating tetradentate-bridging function, and the COO− group binds two adjacent Zn atoms. The IR spectroscopy data for compounds 1 and 3–5 indicate the coordination of the COO−, NOH, and NH functional groups. The excitation and photoluminescence (PLM) spectra of the solid samples of compounds HLNa, HL’Na, 1, and 3–5 were recorded at room temperature. The compounds exhibit blue PLM. The intensity of PLM of the CdII complexes is higher than that of the ZnII complexes, which is a characteristic feature of PLM of the studied compounds.

We have studied the effect of Bi3+ and Ca2+ cation additions and partial Si, P, and V substitutions for Mo on the photoluminescence of NaY1−xEux(MoO4)2 scheelite-like red phosphors. The results demonstrate that the photoluminescence intensity in NaY1 − xEux(MoO4)2 doped with Bi3+ and Ca2+ increases with europium concentration, up to x = 0.5, without concentration quenching. When the atomic fraction of Bi3+ is 0.2, it has a sensitizing effect on Eu3+. Ca2+ doping to an atomic fraction of 0.45 also increases the photoluminescence intensity. Partial Si, P, and V substitutions for Mo have little effect on the photoluminescence intensity.

The complex of CdCl2 with 2-(3,5-dimethylpyrazol-1-yl)-4-methylquinoline (L), Cd2(L)Cl4 (I), is synthesized. According to the X-ray diffraction data, the structure of coordination polymer I is formed by chains in which two crystallographically independent Cd atoms linked by the bridging Cl atoms have different coordination numbers (5 and 6) and different environments. Five Cl atoms form the coordination polyhedron of the Cd(2) atom: a square pyramid (Cd-Cl 2.554(3)–2.689(3) A) completed to a bipyramid by the CI atom at a substantially longer distance of 2.865(4) A. Two Cl atoms and the N atom of quinoline fragment L are arranged in the equatorial plane of the coordination polyhedron of the Cd(1) atom, which is a distorted trigonal bipyramid. The axial vertices are occupied by the N atom of the pyrazole cycle of L and the Cl atom. Five-membered metallocycles CdCN3 are formed upon the coordination of bidentate chelating ligands L. The planes of L of two adjacent chains are parallel (the distances between them are ∼3.5 A), which suggests the π-π interaction between the planes. The luminescence excitation spectrum of compound I has a broad band with λmax = 350 nm. The spectrum of bright blue photoluminescence of compound I (300 K, λexc = 340 nm) contains an intense band with λmax = 420 nm.

Using the single crystal X-ray diffraction data (150 K, Bruker X8 Apex CCD autodiffractometer, MoK α radiation), the crystal structure of the [Cd2L2Cl4]·CH2Cl2 (L = pyrazolylquinoline, the derivative of monoterpenoid (+)-3-carene) compound is determined. Crystals are monoclinic, unit cell parameters are: a = 10.7005(4) A, b = 16.8491(4) A, c = 11.9658(4) A, β = 93.308(1)°, P21 space group. The structure is formed from discrete acentric molecules of a binuclear [Cd2L2Cl4] complex and uncoordinated CH2Cl2 molecules. The Cd2+ ions coordinate N atoms of bidentate chelating ligands L, which leads to the closure of two five-membered chelate CdN3C rings. The coordination sphere of Cd atoms also includes three Cl atoms (two bridging and one terminal), consequently, two CdCl3N2 coordination sites and a Cd2Cl2 metal ring are formed. The Cl3N2 polyhedra have the form of distorted tetragonal pyramids. The CH2Cl2 molecules located in the channels formed by the complexes are linked with them by weak H-bonds. The excitation spectra of L and the CdLCl2 compound contain bands with λmax of 352 nm and 360 nm respectively. At 300 K and λexcit 350 nm, in the photoluminescence spectrum of L a rather intense broad split band with λmax 372 nm and 386 nm is observed. The photoluminescence spectrum of the CdLCl2 compound contains a broad band with λmax 418 nm. The photoluminescence intensity of this compound is significantly lower than that of L.

A series of zinc(II) and cadmium(II) complexes with 4-(3,5-diphenyl-1H-pyrazol-1-yl)-6-(piperidin-1-yl)pyrimidine (L), ZnLCl2, CdLCl2, ZnL2Cl2, CdL2Cl2, CdL2Cl2·0.5Me2CO·1.5H2O and CdL2Cl2·0.5CHCl3·0.5H2O, have been synthesized. The compounds ZnLCl2 and CdLCl2 were obtained in a M:L = 1:1 molar ratio in EtOH solutions, while ZnL2Cl2 and CdL2Cl2 were isolated in a M:L = 1:3 molar ratio in EtOH/Me2CO mixtures. Surprisingly, attempts to crystallize CdLCl2 from EtOH/Me2CO mixture afforded single crystals of a compound, having 1:2 metal-to-ligand stoichiometry, CdL2Cl2·0.5Me2CO·1.5H2O, instead of a complex with 1:1 stoichiometry. At the same time, crystallization of CdL2Cl2 from Me2CO/CHCl3 mixture afforded CdL2Cl2·0.5CHCl3·0.5H2O single crystals. According to X-ray crystal structure data, ZnLCl2, ZnL2Cl2, CdL2Cl2·0.5Me2CO·1.5H2O and CdL2Cl2·0.5CHCl3·0.5H2O complexes have molecular mononuclear structures. The molecules of L adopt bidentate chelating binding mode being coordinated to the metal ions through N2 atom of the pyrazole and N3 atom of the pyrimidine rings. The coordination core of zinc atom in ZnLCl2 complex is a distorted ZnN2Cl2 tetrahedron. The coordination cores of metal atoms in the structures of ZnL2Cl2, CdL2Cl2·0.5Me2CO·1.5H2O and CdL2Cl2·0.5CHCl3·0.5H2O are the distorted cis-MN4Cl2 (M = Zn, Cd) octahedra. In the structure of ZnL2Cl2 double lone pair(N(piperidine))–π(pyrimidine) interactions were observed. The photoluminescent properties of L, ZnLCl2, CdLCl2, ZnL2Cl2 and CdL2Cl2 were studied in the solid state under the same experimental conditions. These compounds were found to display bright blue luminescence. Highest relative intensity of emission was detected for ZnL2Cl2.

The following chiral compounds were synthesized: [ZnLCl2] · EtOH (I) and ZnLCl2 (II), where L is the pyrazolin-5-ol derivative obtained from terpene (+)-3-carene. According to the X-ray diffraction data, the crystal structure of compound I is built of acentric molecules of the mononuclear ZnLCl2 complex and EtOH molecules. In molecules of the complex, the Zn2+ ion is coordinated by two N atoms of the bidentate chelating ligand L and two Cl atoms at the vertices of the distorted tetrahedron. The intermolecular contacts and the hydrogen bonds Cl(1)…H-O(1) between the adjacent ZnLCl2 molecules result in the formation of chains parallel to the y axis. The reactant L and solvate I possess weak photoluminescence in the visible spectral range. Complex II exhibits more intense photoluminescence at λmax = 416 and 517 nm.

It is revealed that at 300 K Sm(Phen)(i-Bu2PS2)3 (I) and Sm(2,2′-Bipy)(i-Bu2PS2)3 (II) complexes have photoluminescence properties typical of the Sm3+ ion. In the spectra, three bands are observed with 7nmax = 564 nm, 600 nm, and 645 nm. Single crystals of Sm(Phen)(i-Bu2PS2)3·MeCN (III) are grown, and the structure of the compound is determined based on the X-ray diffraction data (X8 Apex diffractometer, MoK6h radiation, 7685 F hkl, R = 0.0258). Crystals of III are triclinic, unit cell parameters are a = 11.0554(3) A, b = 15.0446(3)A, c= 15.4849(4)A; 6h = 89.218(1)°, β = 75.555(1)°, γ = 73.484(1)°, V= 2386.6(1)A3, Z=2, ρcalc = 1.391 g/cm3, P1 space group. The structure of III is formed from the molecules of mononuclear complex I and MeCN molecules. A coordination polyhedron of the Sm atom is an N2S6 tetragonal antiprism. It is shown that the structure of III includes dimeric assemblies of the molecules of complex I.

The optically active complex [ZnL1Cl2] (I), where L1 = pyrazolylquinoline (a derivative of monoterpenoid (+)-3-carene) is obtained. Single crystals of compound I are grown and its crystal structure is determined from X-ray diffraction data (X8 APEX diffractometer, MoKα radiation, 3031 Fhkl). The crystals of I are monoclinic; unit cell dimensions are: a = 8.4189(10) A, b = 12.7194(11) A, c = 9.7652(12) A, β = 111.318(3)°, V = 974.14(19) A3, Z = 2, dx = 1.499 g/cm3, space group P21. Complex I is composed of discrete mononuclear molecules. In coordination of Cl atoms and two N atoms of the bidentate cycling ligand L1, a distorted tetrahedral Cl2N2 polyhedron forms at Zn. In the complex molecule, a fragment consisting of five-membered pyrazole and chelate rings, a five-membered carbocycle, and also two six-membered quinoline rings is almost planar. Solid complex I shows strong white photoluminescence at 300 K and λexc = 365 nm in the 400–700 nm range with λmax = 490 nm.

A procedure to synthesize a cadmium(II) chloride complex with bis(benzotriazole-1-yl)methane (L) of the composition [Cd2L(H2O)(C2H5OH)Cl4]n· 1.5nH2O is developed. The compound was studied by single crystal and powder X-ray diffraction. According to the single crystal X-ray data, the complex has a ribbon-polymer structure determined by bidentate bridging type coordination of L to cadmium(II) atoms by N(3) and N(3s’) atoms. Tetramers of cadmium(II) atoms bonded by four bridging fu2- and two fu3-coordinated Cl atoms can be distinguished in the structure. The coordination polyhedron of cadmium(II) atoms is a distorted octahedron. The luminescent properties of L and dehydrated initial complex of the composition [Cd2L(H2O)(C2H5OH)Cl4]n are analyzed. It is shown that L has photoluminescence withλmax = 477 nm in the blue spectral region, and the complex has photoluminescence in the yellow-orange range with λmax = 577 nm at 300 K and λexc = 365 nm.

Complexes Ln(Phen)(C6F5COO)3 (Ln = Tb, Eu; Phen = 1,10-phenanthroline) (I, II) are synthesized. At 300 K these complexes and compounds Ln(C6F5COO)3 · nH2O (Ln = Tb, n = 2; Ln = Eu, n = 1) (III, VI) possess photoluminescence (bright in the case of I and II). In the spectrum of compound I the line at 545 nm (transition 5D4 → 7F5) is most intense, whereas in the spectrum of compound II the most intense is the line at 613 nm (transition 5D0 → 7F2). The replacement of Phen by water decreases the luminescence intensity. The compound [Tb2(H2O)8(C6F5COO)6] · 2C6F5COOH (IV) is synthesized. According to the X-ray diffraction data, in structure IV the molecules of the binuclear Tb(III) complex with the C6F5COOH molecules form a supramolecular ensemble due to hydrogen bonding. The C6F5COO− ligands perform the monodentate and bidentate bridging function, resulting in the opening of the eight-membered cycle Tb2C2O4. The TbO8 polyhedron is a distored tetragonal antiprism. The crystals of the binuclear complex [Tb2(H2O)8(C6F5COO)6] (V) are obtained in which the C6F5COO− ligands are monodentate and tridentate bridging cyclic, which results in the closure of two four-membered cycles TbO2C and one four-membered cycle Tb2O2. The TbO9 polyhedron is a distorted monocapped tetragonal antiprism.

A complex ZnLClb2 (L is 2-(3,5-dimethylpyrazol-1-yl)-4-methylquinoline) was synthesized. According to X-ray diffraction data, the Znp2+ ions in mononuclear molecules of the obtained complex coordinate two N atoms of the bidentate chelating ligand L and two Cl atoms. The coordination polyhedron Cl2Nb2 represents a distorted tetrahedron. In solid state at 300 K, the ligand L exhibits weak photoluminescence in the visible spectral range. The complex ZnLClb2 exhibits bright blue photoluminescence.

The mixed ligand coordination compounds EuL(i-Bu2PS2)2(NO3) (L = Phen, 2,2′-Bipy, 4,4′-Bipy) are synthesized. On the basis of X-ray analysis and IR spectra their structures are elucidated. The complexes containing Phen or 2,2′-Bipy are found to possess photoluminescent property.

The heteroligand complex Nd(Phen){(iso-C4H9)2PS2}2(NO3) (I) was synthesized and its IR spectrum was analyzed. The anions (iso-C4H9)2PS2/− and N3/− act as bidentate cyclic ligands. The single crystals of [Nd(Phen){iso-C4H9)2PS2}3] (II) were obtained on evaporation of a solution of complex I in a mixture CH2Cl2-hexane and were studied by X-ray diffraction. Crystals II are triclinic: a = 10.5509(5); b = 14.7432(8), c = 16.8503(10) A; α = 102.882(2)°, β = 97.211(2)°, γ= 108.087(2)°, V = 2374(2) A3, Z = 2, ρ(calcd.) = 1.332 g/cm3, space group $$ P\bar 1 $$ . The coordination polyhedron of the Nd atom in a separate mononuclear molecule II is a distorted dodecahedron N2S6. The molecules are bound by weak van der Waals and π-π interactions. The photoluminescence spectra of complexes I, II were measured and interpreted.

New cluster compounds [H3O(Ph3PO)3]2[Mo6Cl14] (I) and [H(Ph3PO)2]2[Re6S6Br8] (II) have been prepared by the reaction of a acetonitrile solution of triphenylphosphane oxide Ph3PO with octahedral cluster complexes of molybdenum (H3O)2Mo6Cl14·6H2O and rhenium K2Re6S6Br8, respectively, (with addition of several drops of HBr). The structures and properties of the products were studied by single-crystalX-ray diffraction and NMR and luminescence spectroscopic methods. The compounds studied are characterized by strong hydrogen bonds with O–O distances of 2.45–2.51 A (I) and 2.34–2.41 A (II); unusual H-bonded cationic trimers, [H3O(Ph3PO)3]+, were found in compound I. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

The salts (Bz3NH)3[Mo6OCl13] (I) and (Bz3NH)2[Mo6Cl14] · 2CH3CN (II) were obtained by reacting melted tribenzylamine with cluster Mo compounds. Compound II contains a known cluster anionic complex [Mo6Cl14]2−. Compound I includes novel cluster anionic complex [Mo6OCl13]3−, where one internal Cl atom is replaced by the O atom. Complex II exhibits phosphorescence in a long-wavelength region of visible spectrum.

The [Ca(DMF)6][Mo6Cl14] complex (I) was synthesized by reacting octahedral cluster Mo complex (H3O)2Mo6Cl14·6H2O with the Ca2+ cation in DMF. Analogous reaction carried out in the presence of triphenylphosphine oxide Ph3PO in acetonitrile resulted in [{Ca(OPPh3)4}{Mo6Cl14}] (II). According to X-ray diffraction data, complex I has ionic structure, while the structure of complex II consists of infinite linear chains of the cluster anionic complexes {Mo6Cl14}2− bonded to the cationic Ca complexes {Ca(OPPH3)4}2+. Both complexes exhibit intensive luminescence in red and near-IR regions of the spectrum.

Bi1.6Pb0.4Sr2-xCa2Cu3Oy (x = 0, 0.2, 0.4) high-Tc materials were prepared from oxide-carbonate mixtures and presynthesized mixed oxides. The 2223 superconducting phase was found to be formed most rapidly in thex = 0.4 sample if the Pb-and Ca-containing starting reagents were separated in the initial stage of synthesis. The highest superconducting transition temperature, Tc(R = 0) = 104.3 K, was attained in the stoichiometric 2223 material. The materials were characterized by electrical resistivity, magnetic susceptibility, and Hall effect measurements. The Hall data were used to evaluate carrier concentration and mobility. The 77-K resistivity of the materials was measured as a function of magnetic field.