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10 items
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Structural dissymmetrization of optically anisotropic Grs64±1Adr36±1Sps2 grandite from Meka Presedla (Kopaonik Mt., Serbia)
In this paper, grandite core with Grs64±1Adr36±1Sps2composition was crystallographically studied. This core represents zone A of the macroscopically visiblefive A–E zones of the optically anisotropic Grs58–64 Adr36–42Sps2 grandite. The applied procedure includes the detailed analysis of the powder diffraction patterns, and the Rietveld refinements of the crystal structures in a series of 18 space groups and two mixtures, which were followed by the comparative analysis of the R-values, site occupancy factors, and the bond lengths and angles. Synthesis of all ...Pavle Tančić, Aleksandar Kremenović, Predrag Vulić. "Structural dissymmetrization of optically anisotropic Grs64±1Adr36±1Sps2 grandite from Meka Presedla (Kopaonik Mt., Serbia)" in Powder Diffraction, Cambridge University Press (CUP) (2019). https://doi.org/10.1017/S0885715619000897
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Kristalografsko proučavanje strukturne desimetrizacije granata grosularsko-andraditske izomorfne serije
Pavle I. Tančić (2016-09-21)U ovoj Doktorskoj disertaciji proučavano je pet različitih zona makroskopski zonarnog grandita sa lokaliteta Meka Presedla (Kopaonik, Srbija). Pomoću hemijske i elektronske analize mikroprobe preračunati su relativno visoko homogeni sastavi zona, t.j.: Grs64±1Adr36±1Sps2 (A), Grs62±1Adr38±1Sps2 (B), Grs59±2Adr40±2Sps2 (C), Grs58±2Adr41±2Sps2 (D) i Grs58±1Adr41±1Sps2 (E). Glavne promene u sastavima izražene formulom: Ca2,93-2,97Mn0,05-0,06Mg0,00-0,01Al1,14-1,26Fe3+0,72-0,83Ti0,00-0,02Si2,97-3,02O12 ukazuju da je jedina značajnija varijacija ustanovljena samo kod Al-Fe3+ raspodela u oktaedarskom položaju. Ovakav hemijski sastav je potvrđen i sa matematičkim proračunima iz IC i Raman analiza. Urađena ...Macroscopically zoned grandite, chemical analysis, electron microprobe analysis, Raman, Rietveld, structure, dissymmetrization, space groupPavle I. Tančić. "Kristalografsko proučavanje strukturne desimetrizacije granata grosularsko-andraditske izomorfne serije" in Универзитет у Београду, Универзитет у Београду, Рударско-геолошки факултет (2016-09-21)
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Crystallography and Surface Oxidation of Stoichiometric Arsenopyrite from Šumadija-Kopaonik Pb-Zn/Polymetallic Ore District (Serbia)
Ivana Jelić, Aleksandar Pačevski, Aleksandar Kremenović, Aleš Šoster, Andreja Šestan, Janez Zavašnik (2023)The behaviour and stability of arsenopyrite largely depend on its crystal structure, but studies of crystallography and structural defects are scarce. For clarification, we investigated a series of natural arsenopyrite crystals from the polymetallic Pb-Zn-(±Cu,Ag,Au,Sb,Bi,W) Šumadija-Kopaonik ore district (Serbia) by powder X-ray diffraction (XRPD). Among them, samples from the Drenjak gold mineralisation showed near-stoichiometric FeAsS composition and were further investigated by conventional and high-resolution transmission electron microscopy methods. TEM revealed abundant planar crystallographic defects and epitaxial surface oxide layer ...Inorganic Chemistry, Condensed Matter Physics,General Materials Science, General Chemical Engineering, crystal structure, FeAsS, oxidation, TEM, XRPD... prototype arsenopyrite structure and have further implications for studies on ion incorporation into FeAsS structure and its environmental stability and oxidation mechanisms as a source of anthropogenic As release into the environment. Keywords: FeAsS; crystal structure; oxidation; XRPD; TEM ...
... arsenic sulphide minerals [4]. The ability to incorporate Au in FeAsS structure coincides with the vast amount of (geo)chemical data published, which contrasts sharply with the available structural data [2,5-7]. The ambiguous structure of arsenopyrite has been analysed since the early days of instrumental ...
... structures. The current consensus recognises arsenopyrite”s monoclinic structure, P2/c [9]. The published reports also highlight the possible micro-twinning, and other structural defects as the main obstacle hindering the precise structure analysis, suggesting, additional studies by transmission electron ...Ivana Jelić, Aleksandar Pačevski, Aleksandar Kremenović, Aleš Šoster, Andreja Šestan, Janez Zavašnik. "Crystallography and Surface Oxidation of Stoichiometric Arsenopyrite from Šumadija-Kopaonik Pb-Zn/Polymetallic Ore District (Serbia)" in Crystals, MDPI AG (2023). https://doi.org/10.3390/cryst13020278
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Synthesis, magnetic, thermal and structural properties of Co(II), Ni(II) and Cu(II) complexes containing isophthalato ligands
A series of novel ternary Co(II), Ni(II) and Cu(II) complexes containing 2,20-dipyridylamine (dipya), 2,20-bipyridine (bipy), and 1,10-phenanthroline (phen), as aromatic diamine ligands, and dianion of isophthalic acid (ipht) have been prepared by ligand exchange reactions from diluted H2O/EtOH solutions. The complexes were characterized by elemental analysis, IR spectroscopy, magnetic susceptibility measurements and TG and DSC analysis. Three complexes, Cu(dipya)(ipht)H2O (1), Co(dipya)(ipht)2H2O (2) and Cu(ipht)(phen)2H2O (5) are polymeric with bis-monodentate ipht, while the other two complexes M(bipy)(ipht)4H2O, M@Co(II) (3) and ...комплекси прелазних метала, карбоксилатни лиганди, N-лиганди, кристална структура, магнетна својстваJelena Rogan, Dejan Poleti, Ljiljana Karanović, Zvonko Jagličić. "Synthesis, magnetic, thermal and structural properties of Co(II), Ni(II) and Cu(II) complexes containing isophthalato ligands" in Journal of Molecular Structure, Elsevier BV (2011). https://doi.org/10.1016/j.molstruc.2010.11.024
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A new copper(II) arsenate, Na2Cu3(AsO3OH)4·4H2O containing discrete [Cu3O12]18− units: Synthesis, crystal structure and magnetic properties
Single crystals of the new disodium tricopper(II) tetrakis(hydrogenarsenate(V)) tetrahydrate, Na2Cu3(AsO3OH)4·4H2O were grown under hydrothermal conditions. The compound was characterized by room-temperature single-crystal X-ray diffraction, SEM-EDS analysis, Raman spectroscopy and magnetic susceptibility measurements. Na2Cu3(AsO3OH)4·4H2O represents a new layered structure-type [space group P21/c, a = 8.7089(17), b = 9.7452(19), c = 9.3353(19) Å, β = 92.63(3)°, V = 791.4(3) Å3, Z = 4]. The layers are normal to [100] and are composed of the isolated Cu3O12 units interconnected by AsO3OH coordination ...Na2Cu3(AsO3OH)4•4H2O, хидротермална синтеза, кристална структура, хидрирани хидрокси-арсенати, магнетна својстваTamara Đorđević, Ljiljana Karanović, Zvonko Jagličić. "A new copper(II) arsenate, Na2Cu3(AsO3OH)4·4H2O containing discrete [Cu3O12]18− units: Synthesis, crystal structure and magnetic properties" in Journal of Solid State Chemistry, Elsevier BV (2018). https://doi.org/10.1016/j.jssc.2018.05.024
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Three new Sr-bearing arsenates, hydrothermally synthesized in the system SrO–MO–As2O5–H2O (M2+ = Mg, Cu, Zn)
Tamara Đorđević, Ljiljana Karanović (2018)During systematic research on the mineral-related synthetic arsenates, with particular focus on their structural and spectroscopic classification, three new Sr-containing arsenates Sr2Mg(AsO4)2· 2H2O (1), Sr2Zn4(AsO4)4·H2O (2) and Sr2Cu7(AsO4)6 (3) have been synthesized under low-temperature hydrothermal conditions in the system SrO MO As2O5 H2O (M 2þ = Mg, Zn, Cu). Their crystal structures were determined using room-temperature single-crystal X-ray diffraction data and refined to the following R-values: 1– R1 = 0.025; 2– R1 = 0.030; 3– R1 = 0.035. Compounds ...стронцијум, арсен, арсенати, кристална структура, дифракција рендгенских зрака на монокристалима, хидротермална синтеза, Раманска спектроскопијаTamara Đorđević, Ljiljana Karanović. "Three new Sr-bearing arsenates, hydrothermally synthesized in the system SrO–MO–As2O5–H2O (M2+ = Mg, Cu, Zn)" in European Journal of Mineralogy, Schweizerbart (2018). https://doi.org/10.1127/ejm/2018/0030-2749
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Water in the Alluaudite Type-Compounds: Synthesis, Crystal Structure and Magnetic Properties of Co3(AsO4)0.5+x(HAsO4)2−x(H2AsO4)0.5+x[(H,□)0.5(H2O,H3O)0.5]2x+
In this study, a new cobalt arsenate belonging to the alluaudite supergroup compounds with the general formula of Co3(AsO4)0.5+x(HAsO4)2−x(H2AsO4)0.5+x[(H, )0.5(H2O,H3O)0.5]2x+ (denoted as CoAsAllu) was synthesized under hydrothermal conditions. Its crystal structure was determined by a room-temperature single-crystal X-ray diffraction analysis: space group C2/c, a = 11.6978(8), b = 12.5713(7), c = 6.7705(5) Å, b = 113.255(5)◦, V = 914.76(11) Å3, Z = 2 for As6H8Co6O25. It represents a new member of alluaudite-like protonated arsenates and the first alluaudite-like phase ...супергрупа алуаудита, арсенати прелазних метала, хидротермална синтеза, кристална структура, хидратисани хидрокси-арсенати, стехиометрија, магнетна својстваTamara Đorđević, Ljiljana Karanović, Marko Jagodič, Zvonko Jagličić. "Water in the Alluaudite Type-Compounds: Synthesis, Crystal Structure and Magnetic Properties of Co3(AsO4)0.5+x(HAsO4)2−x(H2AsO4)0.5+x[(H,□)0.5(H2O,H3O)0.5]2x+" in Minerals, MDPI AG (2021). https://doi.org/10.3390/min11121372
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Sinteza i strukturna karakterizacija novih cezijumskih i kalijumskih silikata sa elementima retkih zemalja
Predrag Z. Dabić (2022)Predmet i ciljevi naučnog istraživanja ove doktorske disertacije su sinteza i strukturna karakterizacija novih cezijumskih i kalijumskih silikata sa elementima retkih zemalja. Istraživanja su izvedena u okviru sistema SiO2–REE2O3–XF, gde REE predstavlja trovalentni katjon elementa retkih zemalja (Sc, Y, Sm, Eu, Gd, Ho, Er, Tm, Yb, Lu), dok X predstavlja jednovalentni katjon alkalnih metala (K, Cs). Rad na disertaciji bio je fokusiran na sintezu monokristala, određivanje kristalnih struktura, kao i na kristalografsko i kristalohemijsko ispitivanje sintetisanih monokristala. Monokristali su sintetisani ...alkalni silikati elemenata retkih zemalja, kristalna struktura, sinteza metodom fluksa, rendgenska difrakcija na monokristalu, elementi retkih zemaljaPredrag Z. Dabić. Sinteza i strukturna karakterizacija novih cezijumskih i kalijumskih silikata sa elementima retkih zemalja, Beograd : P. Dabić, 2022
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A new polymorph of Ba(AsO3OH): Synthesis, crystal structure and vibrational spectra
Tamara Đorđević, Ljiljana Karanović (2010)A new monoclinic polymorph of Ba(AsO3OH) was synthesized under hydrothermal conditions. It represents a previously unknown structure type. Its crystal structure was determined from a racemic twin using single-crystal X-ray diffraction data collected at 120 and 293 K [space group P21, a=7.2149(14)/7.2370(2), b=7.7028(15)/7.7133(2), c=21.7385(43)/21.8079(5) Å, β=95.95(3)/96.073(1)1, V=1201.6(4)/1210.51(5) Å3, Z=12]. The crystal structure of P21-Ba(AsO3OH) has a layered character and is built up of four types of regularly alternating layers parallel to (0 0 1). Every AsO3OH tetrahedron is chelating to two Ba atoms and ...Ba(AsO3OH), хидротермална синтеза, структурна анализа монокристала, Раманска спектроскопија, инфрацрвена спектроскопија, водоничне везе, хидрогенарсенати земноалкалних металаTamara Đorđević, Ljiljana Karanović. "A new polymorph of Ba(AsO3OH): Synthesis, crystal structure and vibrational spectra" in Journal of Solid State Chemistry, Elsevier BV (2010). https://doi.org/10.1016/j.jssc.2010.09.027
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Ionothermal synthesis and crystal structure of a new organic–inorganic hybrid compound:catena-poly[bis(1-ethyl-3-methylimidazolium) [hepta-μ-bromido-pentacuprate(I)]]
A new organic-inorganic hybrid compound, catena-poly[bis(1-ethyl-3-methylimidazolium) [μ5-bromido-tri-μ3-bromido-tri-μ2-bromido-pentacuprate(I)]], {(C6H11N2)2[Cu5Br7]}n, has been obtained under ionothermal conditions from a reaction mixture containing Ba(OH)2•8H O, Cu(OH)2•2H2O, As2O5 , 1-ethyl-3-methylimidazolium bromide and distilled water. The crystal structure consists of complex [Cu5Br7]2- anions arranged in sinusoidal {[Cu5Br7]2-}n chains running along the a axis, which are surrounded by 1-ethyl-3-methylimidazolium cations. Three of the five unique Br atoms and one of the three Cu(I) atoms occupy special positions with half-occupancy (a mirror plane perpendicular to the b ...кристална структура, органско-неорганско хибридно једињење, бакар(I) бромид, јонотермна синтеза, 1-етил-3-метилимидазолијум бромид, Cu•••Cu интеракцијеLjiljana Karanović, Dejan Poleti, Tamara Đorđević. "Ionothermal synthesis and crystal structure of a new organic–inorganic hybrid compound:catena-poly[bis(1-ethyl-3-methylimidazolium) [hepta-μ-bromido-pentacuprate(I)]]" in Acta Crystallographica Section C Structural Chemistry, International Union of Crystallography (IUCr) (2014). https://doi.org/10.1107/S205322961402172X