Večja pisava | Manjša pisava

Iskanje po katalogu digitalne knjižnice Pomoč

Iskalni niz: išči po
išči po
išči po
išči po
* po starem in bolonjskem študiju


1 - 4 / 4
Na začetekNa prejšnjo stran1Na naslednjo stranNa konec
Crystal-structure and Mössbauer studies of Li[sub]1.746]Nd[sub]4.494FeO9[sub]9.493
Mihael Drofenik, Irena Ban, Darko Makovec, Darko Hanžel, Amalija Golobič, Ljubo Golič, 2007, izvirni znanstveni članek

Opis: The ▫$Li_1.746Nd_4.494FeO_9.493$▫ (LNF) ternary phase, located in the ▫$Li_2O$▫-rich part of the ▫$Li_2O-Nd_2O_3-Fe_2O_3$▫ system, crystallizes with a cubic unit cell of dimension and the space group Im3m. Refinement on F resulted in R=1.9%. The structure is comprised of a network of corners, edges and faces sharing the coordination polyhedra of neodymium. In between this skeleton the regular octahedra of oxygen-coordinated iron and trigonal prisms of lithium are located. The Mössbauer spectra revealed the presence of ▫$Fe^3+$▫, ▫$Fe^4+$▫ and ▫$Fe^5+$▫ ions distributed on two symmetry-independent lattice positions.
Ključne besede: crystal structure, ternary compounds, single-crystal X-ray diffraction, Mössbauer spectroscopy, iron oxidation state, kristalna struktura, ternarne spojine, rentgenska difrakcija, Mössbauerjeva spektroskopija, rentgenska strukturna analiza
Objavljeno: 01.06.2012; Ogledov: 811; Prenosov: 11
URL Polno besedilo (0,00 KB)

The crystal and molecular structures of two reaction products of geminal dicyano oxirane with thiohydantoine (compound I) and thioxobenzoxazole (compound II)
Ivan Leban, Alenka Majcen Le Marechal, Albert Robert, 1993, izvirni znanstveni članek

Opis: The crystal and molecular structures of two reaction products of geminal dicyano oxiranes with thiohydantoione and thioxobenzoxazole have been determinated from ▫$Mo-K_\alpha$▫ X-ray diffraction data. The two reaction products were: 2H-2-(p-tolyl)-imidazol[1,2-b]thiazole-3,6-dione (compound I) and Z-3-benzoxazole-3-phenyl-2-oxo-2-propanenitrile (compound II) with the following crystal data at 293(1) K: Compound I, ▫$C_{12}H_{10}N_2O_2S$▫, monoclinic ▫$P2_1/c$▫, a=15057(3), b=5.200(3), c=14.724(4) Å, ▫$\beta=104.24(3)°$▫, Z=4; final R and ▫$R_w$▫ values were 0.034 and 0.049 for1647 observed reflexions. Compound II, ▫$C_{16}H{10}N_2O_2$▫, monoclinic, ▫$P2_1/n$▫, a=14.396(3), b=4.326(1), c=21.335(4) Å, ▫$\beta-107.79(1)°$▫, Z=4;final R and ▫$R_w$▫ values 0.040 and 0.053 for 1516 observed reflections.
Ključne besede: organic chemistry, crystal structure, chemical reactions, oxiranes, coordination compounds, structural chemistry
Objavljeno: 05.07.2017; Ogledov: 58; Prenosov: 0
.pdf Polno besedilo (16,17 MB)

Synthesis, crystal structure and magnetic properties of a new hydroxylammonium fluoroferrate
Brina 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: 25.08.2017; Ogledov: 60; Prenosov: 0
.pdf Polno besedilo (198,42 KB)

Two new zinc(II) acetates with 3- and 4-aminopyridine
Brina Dojer, Andrej Pevec, Ferdinand Belaj, Matjaž Kristl, 2015, izvirni znanstveni članek

Opis: The synthesis and characterization of two new zinc(II) coordination compounds with 3- and 4-aminopyridine are reported. They were obtained after adding a water solution of $Zn(CH_3COO)_2$ · $2H_2O$ or dissolving solid $Zn(CH_3COO)_2$ · $2H_2O$ in methanol solutions of 3- and 4-aminopyridine. The products were characterized structurally by single-crystal X-ray diffraction analysis. Colourless crystals of the compound synthesized by the reaction of $Zn(CH_3COO)_2$ · $2H_2O$ and 3-aminopyridine (3-apy), are built of trinuclear complex molecules with the formula $[Zn_3(O_2CCH_3)_6(3- apy)_2(H_2O)_2]$(1). The molecules consists of two terminal $Zn$ atoms, coordinated tetrahedrally, and one central $Zn$ atom, coordinated octahedrally. Colourless crystals, obtained by the reaction of $Zn(CH_3COO)_2$ · $2H_2O$ with 4-aminopyridine (4-apy), consist of a mononuclear complex $[Zn(O_2CCH_3)_2(4-apy)_2]$(2). Hydrogen-bonding interactions in the crystal structures of both complexes are reported.
Ključne besede: zinc(II) acetate dihydrate, aminopyridine, x-ray crystal structure, hydrogen bonds
Objavljeno: 30.08.2017; Ogledov: 21; Prenosov: 0
.pdf Polno besedilo (1,06 MB)

Iskanje izvedeno v 0.03 sek.
Na vrh
Logotipi partnerjev Univerza v Mariboru Univerza v Ljubljani Univerza na Primorskem Univerza v Novi Gorici