I. V. Kalinovskaya

The Fluorescent Properties of Heteroligand Europium Cinnamates

Heteroligand europium cinnamates with nitrogen- and phosphorus-containing neutral ligands were studied by luminescent and X-ray electron spectroscopy. A tendency toward an increase in the electron density on Eu3+ was observed when neutral ligands were coordinated by donor nitrogen atoms. The Δν0, ΔF1, and I(F0)/I(F2) values monotonically decreased as the donor properties of neutral ligands increased because of strengthening of the interaction of Eu3+ with the ligands.

The dispersity and distribution of luminophors in high-pressure polyethylene

Polymers based on high-pressure polyethylene were prepared and activated with europium(III) complexes with carboxylic acids and compositions based on europium-anthranilic acid compounds. According to the electron scanning, atomic, and fluorescence spectroscopic data, luminophor particles showed a heterophase distribution in films. The particles had an average size of 3–30 μm and were shaped as globules.

Crystal and molecular structures and luminescence properties of [Eu(Tol)3]2 · 2DPH complex

The crystal structure of the [Eu(Tol)3]2 · 2DPH complex (Tol = toluic acid anion, DPG = diphenylguanidine) was determined by X-ray crystallography. The coordination polyhedron of a Eu atom [EuO6] (CN = 8) is a distorted square antiprism with nonplanar quadrilateral faces. Diphenylguanidine molecules have been shown to be randomly distributed over the symmetry centers of a unit cell with site occupancies of 0.5. The π stacking interaction C-H…Cg exists in the structure to stabilize it. Luminescent characteristics of the compound have been determined.

Photochemical properties of mixed-ligand complexes europium carboxylates

The photochemical behavior of mixed-ligand complexes of europium carboxylates with nitrogen-and phosphorus-containing neutral ligands of island and dimer types, Eu(L)3 · xD · nH2O and [Eu(L)3 · xD]2 · nH2O (L is the trifluoroacetate, toluate, or cinnamate anion), was studied. During UV irradiation of the complexes of europium carboxylates with 1,10-phenanthroline and 2,2′-dipyridyl, a luminescence buildup was observed. EPR measurements demonstrated that the observed buildup of luminescence from europium occurs in parallel with the increase of the concentration of radical anions formed from neutral ligands.

Luminescence of neodymium(III) carboxylate complexes with different ligands

The spectral and luminescent characteristics of neodymium(III) carboxylate complexes with different nitrogen- and phosphorus-containing neutral ligands were studied and the relationship between the intensity of luminescence and the composition of the coordination sphere was established. The most intensive luminescence of neodymium(III) compounds in the IR region was observed from the complexes with toluic and cinnamic acids.

Crystal and molecular structure and luminescence properties of the europium trifluoroacetate complex with dipyridyl

The crystal structure of [Eu(Dipy)(TFA)3(H2O)3] · Dipy (where TFA− is the trifluoroacetate anion and Dipy is, 2,2′-dipyridyl) has been studied by X-ray diffraction. The coordination polyhedron of the europium atom is a distorted square antiprism [EuO6N2] with the nonplanar quadrilateral faces. The coordinated and non-coordinated dipyridyl molecules are linked pairwise through π stacking interactions into an infinite pile with an overlap of up to 50% of the molecular surface areas. An increase in the luminescence intensity of the compound upon its UV irradiation is explained.

Luminescent and triboluminescent properties of europium(III) hexafluoroacetylacetonate and trifluoroacetate complexes with triphenylphosphine oxide

Crystalline and strongly luminescent complexes of europium hexafluoroacetylacetonate and trifluoroacetate with triphenylphosphine oxide of Eu(HFAA)3 · 2TPPO and [Eu(TFA)3 · 2TPPO(H2O)]2 composition are synthesized that demonstrating triboluminescent properties. It is established that the measured photoluminescence and triboluminescence spectra of these noncentrosymmetric complex compounds are identical, due to the characteristic f-f-luminescence of the europium(III) ion.

Luminescent and photochemical properties of the lanthanide-containing polymer materials

The light-transforming polymer materials have been obtained based on the mixed europium cinnamates, cinnamic acid, and high density polyethylene. The materials exhibit an intensive luminescence in the range of 400–700 nm. The photostability of the materials has been higher than that of polymer materials activated solely with europium compounds. The photolysis of the luminescent polymers has been studied. For the obtained polymer compositions the build-up of europium ion and cinnamic acid luminescence has been observed.

Crystal and molecular structures and luminescence properties of [Eu(Cin)3] n complex

The crystal structure of europium cinnamate of the composition [Eu(Cin)3]n (Cin is cinnamic acid anion C9H7O2−) was determined by X-ray crystallography (a = 22.626(1) Å, c = 7.7330(7) Å, space group R3/c, Z = 3, ρcalc = 1.448 g/cm3). The coordination polyhedron of Eu atoms is a distorted trigonal prism with three centered square faces. The structure is built of infinite polymeric chains [Eu(Cin)3]n running along the c axis and linked by van der Waals and π stacking interactions. Luminescent characteristics of the compound were determined.

Luminescence and magnetic properties of mixed-ligand europium trifluoroacetates

The luminescence and magnetic properties of mixed-ligand europium trifluoroacetates with nitrogen- and phosphorus-containing neutral ligands [Eu(TFA)3 · 3H2O]2 and Eu(TFA)3 · 2D · nH2O were studied (here TFA is the trifluoroacetic acid anion, and D is Phen (1,10-phenanthroline), n = 1; DMF (dimethylformamide), n = 1; or TPPO (triphenylphosphine oxide), n = 3). The molar magnetic susceptibility increased in the series of complex compounds Eu(TFA)3 · 2Phen · H2O < [Eu(TFA)3 · 3H2O]2 < Eu(TFA)3 · 2DMF · H2O < Eu(TFA)3 · 2TPPO · 3H2O. Correlations were found between the luminescent and magnetic characteristics of the complex compounds.