Yu. V. Kokunov

Electronic structure patterns of isoelectronic compounds

Abstract X-ray photoelectron spectra of the valence levels of AO 4 x − anions (A = P, S, Cl, As, Se), AO 3 x − anions (A = S, Cl, I, Se, Te, Br) and AF 6 x − anions (A = Al, Si, As) have been studied. The spectra are interpreted and the electronic structures are considered for the isoelectronic and isovalent compounds.

Influence of synthesis conditions on the properties of 2-pyrimidinecarbonitrile in complexing reactions: Synthesis and structure of the coordination polymer [Ag(C4H3N2CN)NO3] and mononuclear complex [Ag(C4H3N2COOH)2]NO3·H2O

AbstractThe coordination polymer [Ag(C4H3N2CN)NO3] (I) and mononuclear complex [Ag(C4H3N2COOH)2]NO3 · H2O (II) have been synthesized and characterized by X-ray crystallography. The crystals of I are monoclinic, space group Pm, a = 5.364(1) Å, b = 6.631(1) Å, c = 5.648(1) Å, β = 105.68(3)°, V = 193.42(6) Å3, dcalcd = 2.361 g/cm3, Z = 1. The crystals II are triclinic, space group

3D Supramolecular structure of the coordination polymer [Ag(2-MePyz)ReO4]

P\bar 1

Synthesis, 19F, 125Te NMR spectra and crystal structure of NBu4TeF5 and NH4TeF5 (NH4F)0.25 ('(NH4)2TeF6')

, a = 6.859(1) Å, b = 8.872(2) Å, c = 12.825(3) Å, α = 81.29(3)°, β = 86.33(3)°, γ = 69.66(3)°, V = 723.3(3) Å3, dcalcd = 2.002 g/cm3, Z = 2. The structure of I is built of polymeric chains [Ag(C4H3N2CN)]∞+ linked through coordinated anions NO3− into layers (a 2D polymer) perpendicular to the [001] direction. The formation of II is a result of hydrolysis of the carbonitrile group to the carboxyl group (in the presence of metal ions in the solution) and coordination of the ligand to the metal. In II, mononuclear cationic complexes [Ag(N2H3C5OOH)2]+ are linked through H-bonds into supramolecular chains along direction [010]. Hydrogen bonds are also formed between free NO3− anions and water molecules.

Coordination molecular compounds of cadmium(II) iodide with dimethylpyridines

Metal complex [AgL] (I) is synthesized by the reaction of AgNO3 with 3-(5-furyl-1,3,4-oxadiazol-2-yl)acrylic acid (HL, C9H6N2O4), and its crystal structure is determined (CIF file CCDC no. 1426528). The crystals are monoclinic, space group P21/n, a = 4.946(1), b = 20.084(1), c = 9.015(1) Å, β = 92.32(1)°, V = 894.482 Å3, ρcalcd = 2.442 g/cm3, Z = 4. In structure I, pairs of centrosymmetric silver atoms are bound by bidentate-bridging oxygen atoms of two anions L into dimeric blocks. The Ag–Ag distance in the dimer is 2.854(1) Å. The coordination sphere of Ag+ contains two oxygen atoms, one silver atom, and one nitrogen atom of the diazolyl fragment of the adjacent anion. The coordination polyhedron of Ag+ is a strongly distorted tetrahedron. The molecular packing of crystal I is built of infinite ribbons (AgL)n extended along the direction [001]. The photoluminescence spectrum of compound I contains intense bands about 550 nm corresponding to the green spectral range and less intense bands at 425 and 485 nm.

A complex of cadmium(II) iodide with 4-cyanopyridine: Synthesis, crystal structure, and luminescent properties

The complex [Ag(2-MePyz)ReO4] (I) is synthesized, and its structure is determined. The crystals are monoclinic, space group P 21/c, a = 7.234(1), b = 15.451(1), c = 8.036(3) Å, β = 92.56(1)°, V = 897.3(2) Å3, ρcalcd = 3.347 g/cm3, Z = 4. Structure I consists of cationic polymer chains [Ag(2-MePyz)]∞+. Anions ReO4− are weakly bound to Ag+ (Ag...Oaverage 2.693 Å) and join the latter into a supramolecular framework. The Ag+ ion has a linear coordination (NAgN 177.9(2)°, distances Ag-N 2.223(5) and 2.242(5) Å).

Structures of the silver complexes with lutidines according to the NMR data. Crystal structure of [AgNO3(3,5-Lut)2]

Chemistry of coordination polymers and metal-supramolecular ensembles attracts attention due to their structural diversity and potential physical and chemical properties. In this article, the works on the synthesis and structure of coordination polymers of silver published by the authors and coworkers are briefly reviewed and compared with literature data on the structure of coordination polymers of silver published in the recent five years.

Silver complexes with 2-amino-4-methylpyrimidine: Synthesis, crystal structure, and luminescent properties

Abstract 19F and 125Te NMR in different organic solvents and X-Ray investigations NBu4TeF5 (I) and ‘(NH4)2TeF6’ (II) show that TeF5− anion in (I) both solution and the solid state has a square pyramidal structure. No octahedral arrangement of fluorine was found in (II). This compound consists of NH4TeF5 and NH4F molecules, the NH4F being in channels between the layers of NH4TeF5.