N. V. Makarenko

Ion mobility and conductivity in the Li(NH3CH2COO)(NO3) compound

Abstract(7Li, 1H) NMR and impedance spectroscopy methods are used to study the ion mobility and conductivity in a complex of the composition Li(NH3CH2COO)(NO3) (I), which has a layered crystal structure. The character of ion motions in lithium and proton sublattices with temperature variation is considered; the types of motions and temperature ranges in which they occur are determined. It is found that above 350 K the dominant process in the lithium sublattice of the compound is Li+ ion diffusion. Possible migration paths of lithium ions in the lattice of the compound are analyzed. The specific conductivity of the compound is found to be 2.4×10–6 S/cm at 393 K.

Crystal structures of tetrafluoroantimonates(III) of single and double protonated 3-amino-1,2,4-triazolium cations

Crystal structures are determined by X-ray crystallography for tetrafluoroantimonates(III) of single and double protonated 3-amino-1,2,4-triazolium cations of the composition (C2H5N4)SbF4 (I) (monoclinic: a = 4.7723(6) Å, b = 19.643(2) Å, c = 7.6974(9) Å, β = 97.239(2)°, Z = 4, Cc space group) and (C2H6N4)(SbF4)2 (II) (monoclinic: a = 4.7617(3) Å, b = 15.512(1) Å c = 7.4365(5)Å β = 107.706(1)°, Z = 2, P21/n space group). The structure of I is built from complex [SbF4]− anions and single charged (C2H5N4)+ cations; the structure of II is built from the same anion and double charged 3-amino-1,2,4-triazolium cation: (C2H6N4)2+. In the structure, weak interactions Sb…F join the anions in polymeric layers [SbF4]nn− that are assembled in a 3D framework by N-H…F hydrogen bonds. The formation of the double protonated 3-amino-1,2,4-triazolium cation (C2H6N4)2+, found in the crystal structure of II, is observed for the first time.

Crystal structure of the molecular adduct of antimony(III) fluoride with L -phenylalanine

The crystal structure of a newly synthesized molecular adduct of antimony(III) fluoride with L-phenylalanine of the composition SbF3(C9H11NO2) is determined for the first time (monoclinic crystal system: a = 5.8742(1) Å, b = 6.2079(1) Å, c = 15.5401(3) Å, β = 90.741(1)°, Z = 2, P21 space group). The structure consists of SbF3 molecules and L-phenylalanine bound into polymer chains by bidentate bridging carboxyl groups of amino acid molecules. Weak Sb⋯F(3)b bonds organize the adjacent chains into polymer ribbons that are bound into layers by N-H⋯F and N-H⋯O hydrogen bonds.

Structural Transformations and Ionic Mobility in CsSbF3(H2PO4)

Abstract1H, 19F, 31P NMR, DSC, and XRD methods are used to study ionic mobility and structural transformations in the CsSbF3(H2PO4) compound (I). Radical changes in 1H, 19F, 31P NMR spectra above 390 K are associated with a crystalline disordered phase which forms in I at 400–420 K. This phase demonstrates high ionic mobility and further transforms (above 425 K) into the amorphous (glassy) phase. We have determined the types of ionic mobility in this compound and in its amorphous product. According to the NMR data, the diffusion in the proton sublattice of the disordered and amorphous phases proceeds even at room temperature.

Crystal structure of potassium β-tetrafluoroantimonate(III) (β-KSbF4)

AbstractСrystals of the previously unknown polymorph of potassium tetrafluoroantimonate(III) (β-KSbF4) are synthesized and their crystal structure is determined (orthorhombic crystal system: a = 8.1631(5) Å, b = 7.8563(5) Å, c = 6.5396(4) Å, V = 419.40(5) Å3, Z = 4, dcalc = 3.751 g/cm3, F(000) = 424, space group Pmn21). The main structural units of β-KSbF4 within the first coordination sphere are dimer complex [Sb2F8]2– anions formed of trigonal SbF4E and tetragonal SbF5E bipyramids with a common vertex. The previously described α-KSbF4 polymorph consists of tetrameric [Sb4F16]4– complexes formed of SbF5E bipyramids.

Crystal structure and 121,123 Sb NQR parameters of ammonium tridecafluorotetraantimonate(III) NH 4 Sb 4 F 13

Abstract(NH4)Sb4F13 crystals (I) are synthesized and their crystal structure (tetragonal crystal system: a = 9.6431(2) Å, c = 6.5503(2) Å, V = 609.11(3) Å3, Z = 2, dcalc = 4.100 g/cm3, F(000) = 664, space group I4̅) is determined. The main structural units of I are tetranuclear anionic [Sb4F13]− complexes and [NH4]+ cations. The anionic complexes are built of four SbF3 groups linked together by tetrahedral bridging fluorine atom. At room temperature the (NH4)Sb4F13 crystals are isostructural to previously studied МSb4F13 (М = K, Rb, Cs, and Tl). The study of 121,123Sb NQR spectra of compound I is performed in a range of 77-370 K, which shows that when the temperature decreases (<250 K) the substance exhibits piezoelectric properties, as do other compounds of this group, but with a violation of their isostructurality.

Properties of fluoroantimonates(III) complexes with amino acids

Crystalline complex fluoroantimonates(III) with amino acids (glycine, β-alanine, DL-serine, DL-valine, L-leucine, and L-phenylalanine) have been prepared. The complexes stability in aqueous solutions has been studied with the cementation method. 1H NMR studies of aqueous solutions of the amino acids complexes with SbF3 at pH 1–6 and room temperature are reported. Preparation of polycrystalline metal antimony in aqueous solutions of tetrafluoroantimonates(III) complexes with the protonated amino acids has been demonstrated.