1. Synthesis, crystal structure and magnetic properties of a new hydroxylammonium fluoroferrateBrina Dojer, Matjaž Kristl, Zvonko Jagličić, Amalija Golobič, Marta Kasunič, Mihael Drofenik, 2012, izvirni znanstveni članek Opis: This paper reports on the synthesis of a new hydroxylammonium fluoroferrate, with the formula $(NH_3OH)_3FeF_6$, obtained after dissolving iron powder in hydrofluoric acid and adding solid $NH_3OHF$. This new compound has been characterized by chemical and thermal analysis, single-crystal X-ray diffraction, and magnetic measurements. The title compound crystallizes trigonal, R3c, with cell parameters a = 11.4154(2) Å, c = 11.5720(2) Å, Z = 6. The structure consists of $NH_3OH^+$ cations and isolated $FeF_6^{3–}$ octahedra in which the central ion lies on a threefold axis. The oxygen and nitrogen atoms of the hydroxylammonium cations are donors of hydrogen bonds to fluoride anions, resulting in a network of hydrogen bonds between counterions. The effective magnetic moment $µ_{eff}$ = 5.8 BM was calculated and perfectly matches the expected value of high-spin Fe(III) ions. The thermal decomposition of the compound was studied by TG, DSC, and X-ray powder diffraction. Ključne besede: inorganic chemistry, crystallography, coordination compounds, synthesis, crystal structure, characterization of compounds, determination of the structure of compounds, X-ray diffraction, magnetic measurements, thermal analysis, TG, DSC, hydrogen bond, metal complexes, hydroxylammonium fluoromethalatehydroxylammonium, fluoroferrate Objavljeno v DKUM: 25.08.2017; Ogledov: 2076; Prenosov: 70
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2. Synthesis and characterisation of hydroxylammonium fluorochromateMatjaž Kristl, Mihael Drofenik, Ljubo Golič, Amalija Golobič, 2003, izvirni znanstveni članek Opis: Reactions in the system $Cr – NH_3OHF – HF – H_2O$ were investigated. Green crystals of a new compound with the formula $(NH_3OH)_3CrF_6$ have been isolated from the water solution and characterized by chemical analysis. The compound crystallizes as triclinic, P-1, with cell parameters: a = 6.5461(2) Å, b = 6.9347(2) Å, c = 9.4072(3) Å, α = 86.772(1)°, β = 83.804(1)°, γ = 70.283(1)°. The effective magnetic moment, $µ_{eff}$ = 3.82 BM, was calculated from magnetic susceptibility measurements in the temperature range 80-290 K. The thermal decomposition of the compound was studied by TG and DSC analysis. $(NH_3OH)_3CrF_6$ decomposes above 125 °C in three steps and the residue has been identified by X-ray powder diffraction as $α – Cr_2O_3$. Ključne besede: inorganic chemistry, structural chemistry, crystalline structure, coordination compounds, synthesis, inorganic reactions, thermal decomposition, characterization of compounds, TG, DSC, X-ray diffraction, chromium complexes, hydroxylammonium fluoro chromates, crystals Objavljeno v DKUM: 25.08.2017; Ogledov: 1893; Prenosov: 115
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3. Synthesis of nickel and cobalt sulfide nanoparticles using a low cost sonochemical methodMatjaž Kristl, Brina Dojer, Sašo Gyergyek, Janja Kristl, 2017, izvirni znanstveni članek Opis: Nickel and cobalt sulfides are promising materials in different cutting-edge research areas like solar cells, supercapacitors, catalysts, and electrode materials. Nickel and cobalt sulfides with various stoichiometries have been synthesized sonochemically from $Ni(CH_3COO)_2$ ∙ $4H_2O$, $Co(CH_3COO)_2$ ∙ $2H_2O$ and different sulfur precursors using a direct immersion ultrasonic probe. The products were characterized by X-ray powder diffraction, transmission electron microscopy (TEM) including EDX analysis, IR and UV–Vis spectroscopy and elemental analysis. Following products have been obtained: $NiS$, $Ni_3S_4$, $CoS_{1.097}$ and $Co_9S_8$, with average crystallite sizes in the range 7−30 nm. Effects of different reaction conditions on the size, morphology and optical band-gap energy were evaluated. Optical band-gap energies in the range 3.3 eV−3.8 eV were observed for the obtained nanoparticles. Ključne besede: material science, inorganic chemistry, nanotechnology Objavljeno v DKUM: 14.07.2017; Ogledov: 1644; Prenosov: 415
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4. Hydroxylammonium fluorogermanatesIrena Ban, Matjaž Kristl, Mihael Drofenik, Arkadije Popović, 2004, izvirni znanstveni članek Opis: A new hydroxylammonium compound (NH3OH)2GeF6, has been synthesized by the addition of solid NH3OHF to a solution of GeO2 dissolved in 20% HF. The compound was characterized by chemical analysis and X-ray powder diffraction, the thermal decomposition was studied by thermal analysis and mass spectrometry. (NH3OH)2GeF6 crystallizes monoclinic. Two endothermic and two exothermic peaks have been observed on the DSC curve, the decomposition product at 500 °C is GeO2. Ključne besede: inorganic chemistry, synthesis, characterisation, hydroxylammonium fluorogermanates, x-ray powder diffraction, mass spectroscopy, thermal analysis Objavljeno v DKUM: 01.06.2012; Ogledov: 3353; Prenosov: 115
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