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Alkaline tungstate crystals are promising scintillation materials for rare events search, especially for WIMP investigations. Na2W2O7 single crystals doped with 1.0 mol.% chromium and cerium ions were grown from melt by low-thermal-gradient Czochralski technique (LTG Cz) developed at NIIC SB RAS (Novosibirsk, Russia) for obtaining large oxide scintillating crystals of high optical quality. Obtained doped Na2W2O7 single crystals 25 mm in length and 30 mm in diameter. The excitation and emission spectra of the photoluminescence, as well as the decay curves in the temperature range 77—300 K were measured and colorimetric parameters were estimated. Comparative studies of the photoluminescence properties of undoped and doped with Ce3+ and Cr3+ ions Na2W2O7 crystals in the temperature range of 77—300 K have been carried out. It was shown that while the introduction of cerium and chromium ions in the Na2W2O7 crystal lattice didn¢t significantly effect the colorimetric parameters and optical properties, it did increase mechanical hardness of the crystals and decreased the tendency to cracking along cleavage planes. The emission color chromaticity coordinates, сorrelated color temperature and color purity for Na2W2O7:Ce and Na2W2O7:Cr crystals were calculated. The lifetimes of photoluminescence were calculated and a strong temperature dependence of the lifetimes in the range 77—300 K was shown.

Coordination compounds [Eu{Ph2P(O)Pym}2(NO3)3] (1) and [Tb{Ph2P(O)Pym}2(MeOH)(NO3)3] (2) are synthesized by the interaction of Eu(III) and Tb(III) nitrates with diphenyl(pyrimidin-2-yl)phosphine oxide (Ph2P(O)Pym). According to single crystal XRD data, the crystal structures of 1 and 2 consist of molecules of mononuclear complexes. The Ph2P(O)Pym ligand is bidentate chelating and monodentate in complexes 1 and 2 respectively; coordination polyhedra of the Ln atom are N2O8 in 1 and O9 in 2. The presence of C–H⋯O hydrogen bonds between the neighboring molecules of the complexes leads to the formation of dimeric ensembles organized in chains (in 1) and layers (in 2) by weaker hydrogen bonds. The complexes exhibit metal-centered photoluminescence in the solid state at 300 K with long lifetimes of excited states (τ > 1 ms) and luminescence quantum yields φ = 28% and 14% for complexes 1 and 2 respectively.

Six centrosymmetric mononuclear Eu3+ and Tb3+ complexes of the type [LnL2(hfac)3] have been synthesized employing diphenyl(pyridin-2-yl)phosphine oxide (Ph2P(O)Py), diphenyl(pyridimin-2-yl)phosphine oxide (Ph2P(O)Pym), and diphenyl(pyrazin-2-yl)phosphine oxide (Ph2P(O)Pyr) as supporting ligands (L). The complexes [LnL2(hfac)3] (L = Ph2P(O)Py and Ph2P(O)Pyr) comprise an eight-coordinate Ln3+ ion with two monodentate O-donor phosphine oxides and three bidentate hfac− anions. In the [Ln{Ph2P(O)Pym}2(hfac)3] complexes, the Ln3+ ion is nine-coordinated by three bidentate hfac− anions and two Ph2P(O)Pym ligands, one of which is bound to Ln in a N,O-bidentate chelating mode, and the other acts as a monodentate O-donor ligand. The complexes display bright solid-state photoluminescence with emission quantum yields up to 56%. The integral intensity of 5D0 → 7F2 transition in the emission spectra of the Eu(III) complexes strongly depends on the coordination environment of the Eu3+ ion. The asymmetric coordination geometry around Eu3+ results in the large radiative rate constants. The crystals of the Eu(III) and Tb(III) complexes exhibit triboluminescence upon breaking under ambient conditions. The relationship between the triboluminescent properties and crystal structures of the complexes is discussed.

Chiral complexes [Ln((–)-L)2(NO3)3] (Ln = Sm (1), Eu (2), Tb (3)) with an optically active ligand (–)-L containing 1,10-phenanthroline and (–)-borneol moieties and also [Ln((±)-L)2(NO3)3]·1.5MeCN (Ln = Sm (4), Eu (5), Tb (6)) compounds with a racemic ligand (±)-L based on 1,10-phenanthroline and (+)-, (–)-borneol are synthesized. According to single crystal X-ray diffraction data, mononuclear complexes 1-3 are isostructural and crystallize in the non-centrosymmetric space group P43212. The crystal structures of isostructural complexes 4-6 crystallizing in the centrosymmetric space group C2/c contains (+)- and (–)-enantiomeric molecules of the mononuclear complex and MeCN molecules. In complexes 1-6, the (–)-L, (±)-L, and $$\text{NO}_{3}^{-}$$ ligands perform the bidentate chelate function (N4O6 coordination polyhedron of the Ln atom). Complexes 2 and 3 have high quantum yields (φ = 52% and 41%) and long-life luminescence (τ = 1.4 ms and 1.2 ms) in the solid state at 300 K. The luminescence quantum yields of chiral complexes 1-3 are found to several times exceed the quantum yields of racemic complexes 4-6.

Complex ZnLCl2·EtOH·H2O (I) where L is chiral 9,9′-bi-4,5-diazafluorenylidene containing fragments of natural monoterpenoide (–)-α-pinene is synthesized. The crystal structure of I is composed of ZnLCl2 mononuclear complex, solvate EtOH, and H2O molecules. The coordination polyhedron Cl2N2 of the Zn atom is a distorted tetrahedron. L is a bidentate cyclic ligand, involving only two N atoms in the coordination. Complex I is characterized by IR and NMR spectroscopy and its thermal properties are analyzed. In the solid phase, L exhibits photoluminescence is the visible range (λmax = 610 nm).

(Gd1 – xTbx)2O3 (x = 0.04–0.22) films 115 to 150 nm in thickness have been grown on Si and SiO2 substrates by metal organic chemical vapor deposition (MOCVD) using Ln(dpm)3 precursors. After annealing in air at 800°C for removing carbon-containing impurities, the films were sulfided in NH4SCN vapor at temperatures from 700 to 1000°C in an Ar atmosphere until the formation of (Gd1 – xTbx)2O2S oxysulfides. The surface of the films is formed by grains 60 to 200 nm in size. The measured refractive index of the films is 2.2–2.4 and their estimated optical band gap (Eg) is 4.7–5.0 eV. The optical transmission of the films in the visible spectral region (400–750 nm) reaches 78–84%. The highest photoluminescence (PL) intensity in the oxysulfide films produced under identical conditions has been observed at x = 0.05. The blue component of their PL decreases with increasing terbium content and the emission shifts to the green spectral region.

A reaction of a [1,4-C6H4(CH2PPy3)2]Cl2 cationic ligand with CuI (MeCN, r.t.) produces an ionic [C6H4(CH2PPy3)2][C6H4(CH2PPy3Cu3I5)2] complex containing structurally unprecedented [Cu3I5]2– inorganic module in the anionic part. The title complex in the solid manifests a weak deep-red luminescence with λmax = 680 nm and lifetimes of 14 μs and 17 μs at 300 K and 77 K, respectively.

1-D chain coordination polymer (CP) of [Cu2I2(PymPPh2)]n type has been synthesized reacting CuI with 2-(diphenylphosphino)pyrimidine (PymPPh2) under mild conditions (MeCN, r.t.). The structure of the CP is imagined by double-stranded (Cu2I2)n ribbons, the Cu atoms of which are bridged by the PymPPh2 ligands in a 1,3-N,P fashion. At ambient temperature the solid-state CP manifests broad-band photoluminescence (λmax = 530 nm) with the average lifetime of 1.2 µs and quantum efficiency being 15%.

Ionic complexes of the composition [LnL2(NO3)2]2[Ln(NO3)5]3Me2CO (Ln = Sm (1), Eu (2), Tb (3), Dy (4)) with an optically active ligand L containing 1,10-phenanthroline and (+)−3-carene moieties are synthesized. According to the X-ray crystallographic data, the crystal structure of compound 2 is composed of complex [EuL2(NO3)2]+ cations (N6O4 polyhedron) and complex [Eu(NO3)5]2− anions (O10 polyhedron), and also Me2CO molecules. The L and NO3 ligands perform both tridentate and bidentate chelating functions respectively. Complexes 1–4 are isostructural and crystallize in the non-centrosymmetric space group P1; their magnetic properties are studied in the temperature range 2–300 K. The μeff values for 1–4 at 300 K are 3.14 μB, 6.08 μB, 16.76 μB, and 18.30 μB respectively and are typical of Ln3+ ions. For complex 3 significant anisotropy results in a nonlinear field dependence of the magnetization at 2 K. Complexes 1–4 exhibit metal-centered orange (Sm3+), red (Eu3+), green (Tb3+), and yellow (Dy3+) luminescence in the solid state at room temperature. Luminescence quantum yield decreases for solid samples in the order 2 > 1 > 3 ≈ 4.

Complexes [Zn(L)Cl2] (I), Cu(L)Cl2 ∙ H2O (II), Zn(L1)Cl2 ∙ 0.5H2O (III), and Cu(L1)Cl2 ∙ 0.5H2O (IV) (where L and L1 are the diaminopropylene and diaminoethylene derivatives of deoxycholic acid, respectively) are synthesized. The structure of mononuclear complex I is determined by X-ray structure analysis (CIF file CCDC no. 1875305). The coordination polyhedron of the Zn atom (Cl2N2) is a distorted tetrahedron. According to the X-ray diffraction data, the crystals of compounds III and IV are isostructural. It is shown by IR spectroscopy that the structures of complexes II–IV are similar to that of complex I. In the solid phase, compounds L and L1 possess photoluminescence in the visible spectral range (λmax = 440 and 415 nm, respectively). Complex formation with Zn2+ ions does not change the photoluminescence properties of L and L1.

2-Ehtylthiopyridine (L) reacts with CuI (MeCN, r.t.) to afford a 1D chain coordination polymer (CP), [Cu2I2(L)]n in a 75% yield. The latter consists of double-stranded (Cu2I2)n ribbons ligated on both sides by 2-ehtylthiopyridines in a 1,3-N,S bridging manner. In the solid state at 298 K, this CP displays yellow-green photoluminescence (λmax = 550 nm) with a short lifetime (2.4 µs) and a moderate emission quantum yield (16%).

Zinc(II) complexes with 1,10-phenanthroline and tetrafluoroterephthalate and octafluorobiphenyl 4,4′-dicarboxylate anions have been synthesized. According to the IR spectral data, the complexation involves coordination of the metal ion to the nitrogen atoms of phenanthroline and carboxylate oxygen atom of the acid anion. The complexes show photoluminescence in the visible region of the spectrum. The structure of the complex salt [Zn(H2O)6][Zn(H2O)4(L2)2] · H2O, where L2 is octafluorobiphenyl-4,4′-dicarboxylate anion (monodentate ligand), has been determined by X-ray analysis.

Mononuclear zinc(ii) and cadmium(ii) complexes, ZnLCl2 (1), CdLCl2 (2), ZnL1Cl2·2H2O (3), and CdL1Cl2·2H2O (4), with chiral ligands containing a 2,2'-bipyridine moiety and natural terpene (+)-limonene (L) or (+)-3-carene (L1) moieties were synthesized. In these complexes the L and L1 ligands are shown to coordinate Zn2+ and Cd2+ ions through the 2,2'-bipyridine moiety. The acetamide group of the ligands interacts with M2+ ions by forming NM2+ and C[double bond, length as m-dash]OM2+ contacts and N-HCl hydrogen bonds with coordinated Cl- ions. In solutions the complexes have several conformers differing by the degree of the turn of the acetamide moiety relative to the ligand core and the type of its interaction with the coordination core. The ligands and complexes exhibit luminescence with the quantum yield increasing in the order: ligandcadmium(ii) complexzinc(ii) complex. The complexes 3 and 4 demostrate excitation wavelength independent single-channel fluorescence. As opposed to 3 and 4, the complexes 1 and 2 demonstrate excitation wavelength dependent emission with nanosecond and microsecond lifetimes of the excited states. According to our TD-DFT calculations, an interplay of ligand centered and halide to ligand transitions facilitates two deactivation channels in 1 and 2: S1-S0 and T1-S0.

A series of red-emissive {Cu4I6} clusters have been synthesized from alkyl-tris(2-pyridyl)phosphonium halides, [R-PPy3]Hal, and CuI. The size of the alkyl substituent (R) has a dramatic impact on the structure of the clusters assembled. [Me-PPy3]I salt reacts with CuI (1 : 2) to give the ionic [Cu(Me-PPy3)I]2Cu2I4 complex consisting of the scorpionate [Cu(N,N′,N′′-Me-PPy3)I]+ cation. Under similar conditions, [Pr-PPy3]I forms the zwitterionic [Cu4I6(Pr-TPP)2] complex containing an unusual stepwise [Cu4I6] cluster core. The use of [Bu-PPy3]I or [Bn-PPy3]I in this reaction leads to zwitterionic [Cu4I6(R-TPP)2] complexes, in which a linear-shaped [Cu4I6] module appears. Photophysical studies supported by TD-DFT computations have revealed that the title complexes in the solid state at 298 K exhibit a red photoluminescence (λemmax = 620–650 nm) with short lifetimes (0.04–2.10 μs), which are assigned to the thermally activated delayed fluorescence (TADF) mixed with the cluster centered (3CC) phosphorescence. The compounds synthesized are the first red-emitting representatives of the recently discovered family of zwitterionic CuI-based complexes (so-called “AIO” structures).

New chiral 1,10-phenanthroline-derived ligands containing fragments of (+)-3-carene (L1) and (+)-limonene (L2) natural monoterpenoids and their complexes Zn(L1,2)Cl2·1.5H2O, Cd(L1,2)Cl2·nH2O, Zn(L1)Br2·2H2O, and Cd(L1)Br2·2H2O were synthesized. According to NMR and IR spectroscopy data, a conclusion was made about the polynuclear structure of the compounds obtained. Luminescent properties of the compounds obtained were investigated. Lifetimes of the excited states and luminescence quantum yields (φf) were determined. For free ligands, blue fluorescence was observed. In the case of Zn(II) and Cd(II) complexes, luminescence appeared in the green region of the spectrum.

Diamond crystals from the Istok (25 crystals) and Mayat (49 crystals) placers were studied using the EPR-, IR-, and luminescence methods. The total content of impurity nitrogen in forms of A-, B-, and C (P1)-centers ranges from 50 to 1200 ppm. According to the EPR-spectroscopy, the presence of nitrogen C(P1), N3V nitrogen-titanium OK1, N3, NU1 impurity centers was established in the investigated crystals. Crystals from the Istok placer contain the OK1, N3, NU1 centers, but luminescence attributed to the oxygen-containing centers is absent in the region of 610-670 nm. For the Mayat placer crystals, the reverse situation was observed. The luminescence ascribed to the oxygen-containing centers was detected for 17 crystals, but there were no OK1, N3 and NU1 centers according to the EPR- and luminescence. This result contradicts the arguments of a number of authors about the oxygen nature of these defects. For 5 crystals from the Mayat placer, the nickel impurity was registered. This indicates the presence of ultrabasic paragenesis diamond crystals in this placer.

An attempt is made to explain the causes of coloration of LiB3O5 crystals after their long-term operation as laser elements. By EPR and optical spectroscopy the impurity and radiation centers are studied in as-grown LiB3O5 crystals and in the crystals whose color appeared after the long-term operation as laser elements. In a number of as-grown crystals a copper impurity is detected. EPR spectral parameters and the structural positions of Cu2+ ions are found. Defect formation features in electron irradiated as-grown LiB3O5 crystals and in the most colored regions of crystals of spent laser elements are analyzed. It is shown that in both growth crystals and crystals after long-term operation as laser elements the same set of radiation defects is observed: oxygen O– in the interstitial position, an O– hole center in the crystal structure, and the B2+ electron center due to the removal of an oxygen atom near the lithium vacancy. The only distinction is that the concentration of these radiation defects in crystals long used as laser elements is higher than that in growth ones by an order of magnitude. The results obtained enable the conclusion that the cause of coloration of LiB3O5 crystals is photo-induced diffusion of lithium atoms and their capture by cation vacancies in the dark part of the crystal, which provides the formation and accumulation of lithium vacancies in the region where the laser beam passes.

Complexes ZnLCl2 (I) and [CdLCl2] n (IV), where L is chiral bis-pyridine containing fragments of natural monoterpenoide (–)-α-pinene are synthesized. Single crystals of [ZnLCl2]·CH2Cl2 (II), [ZnLCl2]·i-PrOH (III), and IV compounds are grown. The crystal structures of II and III are composed of mononuclear ZnLCl2 complex molecules and solvate CH2Cl2 and i-PrOH molecules; the coordination polyhedron of the zinc atom Cl2N2 is a distorted tetrahedron. According to the single crystal XRD data, complex IV is a 1D coordination polymer; the coordination core CdN2Cl4 is a distorted octahedron and Cl atoms are bridging ligands. In the structures of II, III, and IV the L molecule functions as a bidentate chelate ligand. In the solid phase, complexes I and IV exhibit photoluminescence in the visible range (λmax 505 nm and 460 nm respectively). The band intensity in the photoluminescence spectra of I and IV complexes considerably exceeds the band intensity in the spectrum of free L.

(Gd x Y1–x )2O3:Eu3+ (11–14 at % Eu) phosphor films ≤150 nm in thickness have been grown by Ln(dpm)3 chemical vapor deposition on Si(100) substrates, and the chemical and phase compositions of the films have been determined. We have studied photoluminescence spectra of the films and the exact distribution of the Eu3+ activator ions over the cation sites of the solid solutions.

Reactions between Zn(II) dihalides and 2-halogen-substituted pyridines 2-XPy result in a series of heteroleptic molecular complexes [(2-XPy)2ZnY2] (Y = Cl, X = Cl (1), Br (2), I (3), Y = Br, X = Cl (4), Br (5), I (6), Y = I, X = Cl (7), Br (8), and I (9)). Moreover, 1–7 are isostructural (triclinic), while 8 and 9 are monoclinic. In all cases, halogen bonding plays an important role in formation of crystal packing. Moreover, 1–9 demonstrate luminescence in asolid state, for the best emitting complexes, quantum yield (QY) exceeds 21%.

Photoluminescent Eu(III) compounds with anions of the acid 3-CF3C6F4COOH (LH) of composition Eu(L)3·2H2O and Eu(phen)(L)3 were synthesized. The photoluminescence intensity of the complex Eu(phen)(L)3 is higher than that of a similar Eu(III) complex containing anions of the acid 4-CF3C6F4COOH as ligands.

Films of hydrogenated SiC x N y O z :H obtained by plasma-enhanced chemical vapor deposition from a mixture of 1,1,3,3-tetramethyldisilazane with oxygen and nitrogen (TMDS+ O2+xN2) in the temperature range 373-973 K are nanocomposites in whose amorphous part nanocrystals belonging to phases of the Si–C–N: α-Si3–x C x N4 system and graphite are distributed. A change in the chemical composition of gas mixtures enables the preparation of SiC x N y O z :H films with a broad variation range of functional properties, such as the 1.45-2.15 variation of the refractive index; the controlled transparency (T ~ 92-99.7%) in the UV, visible, and IR spectral ranges; tunable characteristics of the band gap (3.5-5.4 eV), and dielectric constants (5.2-5.8).

New polymeric cadmium complexes, α-[CdLCl2]n (1), [CdL2Cl2]n (2) and β-[CdLCl2]n (3) (L = 4-amino-2,1,3-benzothiadiazole), were obtained as products of the reaction of CdCl2 with L. The synthetic procedures allowing isolation of pure 1–3 were optimized. The structures of 1–3 were established by single-crystal X-ray diffraction and the compounds were characterized by UV–Vis and IR spectroscopy. In these compounds, L is either μ-bridging (1) or terminal (2 and 3). The UV–Vis spectra of the complexes in the solid state resemble that of free L. However, coordination of L leads to a significant shift of emission in photoluminescence spectra from yellow (free L) to red (1–3).

Solid phases of the [Eu(Phen)(i-Bu2PS2)2(NO3)]–[Tb(Phen)(i-Bu2PS2)2(NO3)] binary system are synthesized. The results of X-ray diffraction phase analysis and photoluminescence measurements allow the synthesized isostructural phases to be classed with substitutional solid solutions. The photoluminescence measurements revealed Tb(III)→Eu(III) energy transfer which induces Eu3+ luminescence.

By the low-gradient Czochralski method, both undoped and copper ion activated Li2–2xMg2+x(MoO4)3 crystals are grown. The charge state and structural position of impurity copper ions are determined using EPR. Investigations of the luminescence properties reveal that luminescence with a maximum at λ = 520 nm is observed for Li2–2xMg2+x(MoO4)3 crystals. A decrease in the temperature increases the intensity of this luminescence. It is found that the doping of Li2–2xMg2+x(MoO4)3 crystals with copper ions also increases the luminescence intensity with a maximum at λ = 520 nm. It is supposed that cation vacancies, which provide the charge compensation when copper ions substitute for lithium ions, are responsible for the luminescence.

The nucleation of CdS particles on the surface of polystyrene supports from aqueous ammonia—thiourea solutions was studied. The increment in the mass of nanoparticles on the support with time was determined. The degree of binding of Cd(II) ions into sulfide on the surface (support area 14 cm2, solution volume 3.7 cm3) after 3 h at 50°C was 2.2% of their total amount. The results agreed well with those of model calculations for spherical (for small times) and ellipsoid particles at a constant surface concentration. The nanoparticles that formed in solution were not involved in the formation of surface films on polystyrene supports. The photoluminescent properties of the obtained films were studied.

Heteroleptic Zn(II) 3,5-iodosalicylate (DISA) complexes of general formula [Py2ZnDISA2] (Py = 3-methyl (1), 4-methyl (2), 3,5-dimethyl (3), 3,4-dimethyl (4) and 3-bromopyridine (5), respectively) were prepared and characterized by X-ray diffractometry and thermogravimetric analysis. All complexes demonstrate luminescence in blue region with quantum yields varying in 1.45–2.6% range.

A novel β-ketoimine-functionalized 2,1,3-benzothiadiazole (4-(2,1,3-benzothiadiazole-4-ylamino)pent-3-en-2-one, L2H) was synthesized and used as chelating ligand for the complexation with Zn(II) (complex ZnL2). The spectroscopic and photophysical properties of L2H and ZnL2 as well as those of previously described 4-amino-2,1,3-benzothiadiazole (L1) and its complex ZnL1 have been thoroughly studied in the crystalline state and solution. The UV-Vis absorption spectra of free ligands L1, L2H and its deprotonated form L2−, and complexes ZnL1 and ZnL2 were assigned on the basis of TD-DFT calculations. In contrast to ZnL2 having conventional single-band fluorescence, ZnL1 demonstrates a broad double-band purple-white fluorescence spanning the entire visible region. On the basis of careful spectroscopic studies the second band of this unusual fluorescence spectrum was attributed to the presence of traces of free ligand L1 in the crystals of complex ZnL1. The energy transfer from the excited state of ZnL1 to a free ligand L1 was revealed.

Tris(2-pyridyl)phosphine oxide reacts with CuSCN to form a variety of luminescent complexes, depending on the specified metal-to-ligand ratio and the solvent used, viz. mononuclear [Cu(N,N′,N′′-Py3PO)(NCS)], dinuclear (N,N′-Py3PO)Cu(SCNNCS)Cu[(N,N′-Py3PO)], their co-crystal (2:1, correspondingly) and trinuclear {Cu(NCS)[SCNCu(N,N′,N′′-Py3PO)]2}. In the solid state, these complexes feature red-orange emission upon UV photoexcitation. The reaction of tris(2-pyridyl)phosphine with CuSCN quantitatively produces an almost insoluble coordination polymer, [Cu(Py3P)NCS]n, which exhibits bright green emission. The synthesized compounds are the first members of the hitherto unknown family of Cu(I) thiocyanate complexes supported by tripodal ligands.

A metal-organic coordination polymer of the formula [Li3(btc)(H2O)] (1a) (H3btc is the trimesic acid, C6H3(COOH)3) was obtained upon heating a mixture of LiBH4 and H3btc in ethanol. The structure was established by single crystal X-ray diffraction study. The studies by TGA show that polymer 1a loses the coordinated water at T ≥ 250 °C, whereas the metal-organic framework of lithium trimesate disintegrates only above 500 °C. The luminescence spectra showed a considerable (5-fold) increase in luminescence intensity and a bathochromic shift upon dehydration of 1a.

The complexes [Cu(HL)Cl] · 0.25H2O (I), [Cu(HL1)Cl] · 0.5H2O (II), [Ag(HL)] · 0.5H2O (III) were obtained; HL– and (HL1)– are the anions of the chiral N-substituted aminoacetic acid derivatives containing the natural monoterpenes (+)-3-carene and (–)-α-pinene, respectively. The µeff values for paramagnetic complexes I and II are 1.92 and 1.81 µB, respectively. Single crystals of the coordination 1D polymer [Cu(HL)Cl · 2H2O]n (IV) were grown. According to the X-ray diffraction data (CIF file CCDC No. 1035219), the crystal structure of complex IV is made up of the zigzag chains [Cu(HL)Cl]n and water molecules. The coordination polyhedron of the Cu atom is a distorted square pyramid (ClN2O2). The anion HL– acts as a chelating and bridging tetradentate ligand coordinated through the N atoms of the NH and NOH groups as well as through the O atoms of the COO–groups linking two adjacent Cu atoms together. The IR spectra of complexes I and II also provide evidence for the coordination of the functional COO–, NOH, and NH groups. In complex III, the coordination sphere of the Ag atom is made up of the O atoms of the COO–group. Complex III shows weak green photoluminescence (λmax = 530 nm).

Octafluorobiphenyl-4,4′-dicarboxylic acid (H2L) and its complexes with Tb(III) and Eu(III) [Ln2(H2O)4(L)3·3H2O and Ln2(phen)2(L)3·2H2O] have been prepared; their structure has been elucidated from IR spectroscopy and X-ray diffraction analysis data. Thermal properties of the compounds have been studied. The complexes of Tb(III) and Eu(III) exhibit green and red photoluminescence, respectively.

Nonaqueous electrophoresis reveals that the electrokinetic potential of CdS nanoparticles increases slightly (85–120 mV) along with the concentration (0–5 × 10−3 M) of sodium bis(2-ethylhexyl) sulfosuccinate (AOT) in n-decane, while negatively charged SiO2 particles acquire positive charge (switching from −75 up to +135 mV). The energies of interparticle interactions in CdS-CdS and CdS-SiO2 systems are calculated from these parameters and the literature values of the Hamaker constants according to the Deryaguin-Landau-Verwey-Overbeek (DLVO) theory. It is concluded that the presence of a minimum (2.5 k B T) on the potential dependences of the CdS-SiO2 system indicates the formation of CdS-SiO2 aggregates electrostatically bound by heterocoagulation at low concentrations of AOT. The luminescent properties of the obtained ultrafine CdS-SiO2 powders depend on the CdS content.

The complex Pd(HL)Cl2 (I) was obtained (HL is the anthracene-containing chiral α-amino oxime derived from the natural monoterpenoid (+)-3-carene). Single crystals of its solvate [Pd(HL)Cl2] · 0.33EtOH (II) were grown. According to X-ray diffraction data (CIF file CCDC no. 1008947), the crystals are built from mononuclear molecules of complex I and uncoordinated EtOH molecules. The coordination environment of the Pd atom in complex I (PdCl2N2) makes up a distorted square (trapezoid). The compound HL acts as a chelating bidentate ligand. The [Pd(HL)Cl2] and EtOH molecules are united into chains through weak hydrogen bonds. The photoluminescence (PL) of HL and the system ZnCl2-HL in acetonitrile was studied. The emission spectra show three bands at 394, 415, and 440 nm. The photoluminescence of the system ZnCl2-HL in solution is more intense than that of HL. A study of the system ZnCl2-HL by the molar ratio method in conjunction with emission spectroscopy suggests the formation of the complex Zn(HL)Cl2 in acetonitrile.

Five compounds of the composition Ln(2,2′-Bipy)(C4H8NCS2)3 · 0.5CH2Cl2 (Ln = Sm (I), Eu (II), Tb (III), Dy (IV), and Tm (V); 2,2′-Bipy = 2,2′-bipyridine) are synthesized. According to the X-ray diffraction data (CIF file CCDC 986259), the crystal structure of compound I consists of molecules of the mononuclear complex [Sm(2,2′-Bipy)(C4H8NCS2)3] and solvate molecules CH2Cl2 (2 : 1). The coordination polyhedron N2S6 of the Sm atom is a distorted tetragonal antiprism. The X-ray diffraction analysis shows that compounds I–V are isostructural. The magnetic properties of compounds I–V are analyzed in the temperature range from 2 to 300 K. At 300 K compounds I and III are photoluminescent in the visible spectral range. The photoluminescence intensity of compound I considerably exceeds that of complex III.

It is found that diffraction patterns of complexes I–V of the composition [Ln(Phen)(C4H8NCS2)3] (Ln = Sm, Eu, Tb, Dy, and Tm respectively) are similar. Single crystals of [Dy(Phen)(C4H8NCS2)3]·3CH2Cl2 (VI) obtained are. According to the X-ray crystallographic data, in the structure of VI the unit cell contains two crystallographically independent molecules of the [Dy(Phen)(C4H8NCS2)3] complex and six CH2Cl2 molecules. The N2S6 coordination polyhedron of the Dy atom is a distorted square antiprism. In the range of 2–300 K the magnetic properties of complexes I–V are studied. It is found that complex III passes to the magnetically ordered state; the spontaneous magnetization at 2 K is 24 600 G·cm3/mol. At 300 K compounds I–IV exhibit photoluminescence in the visible spectral range. It is found that the photoluminescence intensity of complex I is several times higher than the photoluminescence intensity of complexes II–IV.

ZnLCl and [H2L]2[ZnCl4], based on 2-(1-hydroxy-4,5-dimethyl-1H-imidazol-2-yl)pyridine (HL), have been synthesized. There is a short intraionic O–H···N hydrogen bond between the hydroxyimidazolyl and pyridyl of H2L+ cations (N···O 2.608(2) A) in the structure of [H2L]2[ZnCl4]. The formation of this rather strong hydrogen bond is confirmed by IR spectroscopy through a broad band at 3200–2200 cm−1 and a band at 1655 cm−1. HL crystallizes in the form of a hemihydrate, HL·0.5H2O. HL assemble into infinite helical chains due to N–H···O intermolecular hydrogen bonds between the NH of imidazole and O of the N-oxide (O···N 2.623(2) A). An unusual mid-IR pattern with three broad bands at 3373, 2530, and 1850 cm−1 is typical for strong hydrogen bonds, explained by resonance-assisted hydrogen bonding occurring in the helical chains. On cooling to 5 K, noticeable changes in the IR spectra of [H2L]2[ZnCl4] and HL·0.5H2O were observed. ZnLCl and [H2L]2[ZnCl4] exhibit bright photoluminescence with maxima of emission at 4...

A series of mononuclear heteroleptic copper(I) halide complexes, [CuL(PPh3)X] (X = Cl, Br, I), based on 4-(3,5-diphenyl-1H-pyrazol-1-yl)-6-(piperidin-1-yl)pyrimidine (L) and triphenylphosphine, have been synthesized by reaction between CuX (X = Cl, Br, I), L and PPh3 in a molar ratio of 1/1/1 in MeCN solutions. The copper atom, showing the distorted tetrahedral environment, is bound by the N,N-chelating ligand L, triphenylphosphine and a halide ion. The complexes [CuL(PPh3)Cl] and [CuL(PPh3)Br] are isostructural. In CH2Cl2 solutions, L and the complexes [CuL(PPh3)X] (X = Cl, Br, I) display a luminescence band with λ(max) = 377 nm and a lifetime of 1.9 ns (ligand-based luminescence (LL*)). However, the complex [CuL(PPh3)I] has an additional weak luminescence band with λ(max) = 681 nm and a lifetime of 96 ns of (3)MLCT origin. In the solid state, L shows the splitting of the luminescence band to λ(max) = 365 and 384 nm and a slight increase of the lifetime to 2.66 ns. Solid samples of the complexes [CuL(PPh3)X] demonstrate (3)MLCT luminescence bands at 620 nm (X = Cl), 605 nm (X = Br) and 559 nm (X = I) with lifetimes in the range 3.6-11.2 μs, whereas the LL* band (377 nm) is absent. Quantum yields and rate constants of radiative and nonradiative processes were determined in CH2Cl2 solutions and in the solid state for all complexes. The luminescence quantum yield and lifetimes for the solid samples increase in the order [CuL(PPh3)Cl] < [CuL(PPh3)Br] < [CuL(PPh3)I]. This is due to the increase of radiative decay and simultaneous suppression of nonradiative decay. The complex [CuL(PPh3)I] shows a high quantum yield of 29.4% and an excited state lifetime of 11.2 μs.

Heteroligand complexes Tm(L)(iso-Bu2PS2)2(NO3) (L = 2,2′-Bipy (II), Phen (III)) are synthesized. According to the X-ray phase analysis data, complex III is isostructural to mononuclear compound [Dy(Phen)(iso-Bu2PS2)2(NO3)] including, according to the X-ray diffraction data, a coordination polyhedron DyN2O2S4 (distorted dodecahedron). Single crystals of compounds [Ln(2,2′-Bipy)(iso-Bu2PS2)2(NO3)] · C6H6 (Ln = Tm (IV), Tb (V)) are obtained. An X-ray diffraction analysis shows that the crystal structures of these isostructural compounds are formed by molecules of mononuclear complexes [Ln(2,2′-Bipy)(iso-Bu2PS2)2(NO3) and uncoordinated C6H6 molecules. In complexes IV and V, the ligands [Ln(2,2′-Bipy)(iso-Bu2PS 2 − , and NO 3 − are bidentate-cyclic. The coordination polyhedron LnN2O2S4 is a distorted dodecahedron. Complexes II and III possess photoluminescence in the visible spectral range (λmax = 478 and 477 nm, respectively).

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.

Complexes ZnL1Cl2, CdL1Cl2, ZnL21Cl2·1.5H2O, CdL21Cl2·2H2O, CdL21Cl2·MeOH·H2O [L1 = 2-(4,5-dimethyl-1H-imidazol-2-yl)pyridine] and inner-complex compounds ZnL22·2H2O, CdL22 [HL2 = 2-(1-hydroxy-4,5-dimethyl-1H-imidazol-2-yl)pyridine] were synthesized. The complexes exhibit bright photoluminescence in the blue region of the spectrum, with the intensity exceeding this characteristic of the compounds L1 and HL2. Compound L1 in aqueous solution is a potential chemosensor for the determination of zinc and cadmium.

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.