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Title: Eu{sub 3}F{sub 4}S{sub 2}: Synthesis, crystal structure, and magnetic properties of the mixed-valent europium(II,III) fluoride sulfide EuF{sub 2}.(EuFS){sub 2}

Abstract

Using the method to synthesize rare-earth metal(III) fluoride sulfides MFS (M=Y, La, Ce-Lu), in some cases we were able to obtain mixed-valent compounds such as Yb{sub 3}F{sub 4}S{sub 2} instead. With Eu{sub 3}F{sub 4}S{sub 2} another isotypic representative has now been synthesized. Eu{sub 3}F{sub 4}S{sub 2} (tetragonal, I4/mmm, a=400.34(2), c=1928.17(9) pm, Z=2) is obtained from the reaction of metallic europium, elemental sulfur, and europium trifluoride in a molar ratio of 5:6:4 within seven days at 850 deg. C in silica-jacketed gas-tightly sealed platinum ampoules. The single-phase product consists of black plate-shaped single crystals with a square cross section, which can be obtained from a flux using equimolar amounts of NaCl as fluxing agent. The crystal structure is best described as an intergrowth structure, in which one layer of CaF{sub 2}-type EuF{sub 2} is followed by two layers of PbFCl-type EuFS when sheeted parallel to the (001) plane. Accordingly there are two chemically and crystallographically different europium cations present. One of them (Eu{sup 2+}) is coordinated by eight fluoride anions in a cubic fashion, the other one (Eu{sup 3+}) exhibits a monocapped square antiprismatic coordination sphere with four F{sup -} and five S{sup 2-} anions. Although the structural ordering of themore » different charged europium cations is plausible, a certain amount of charge delocalization with some polaron activity has to take place, which is suggested by the black color of the title compound. Temperature dependent magnetic susceptibility measurements of Eu{sub 3}F{sub 4}S{sub 2} show Curie-Weiss behavior with an experimental magnetic moment of 8.19(5) mu{sub B} per formula unit and a paramagnetic Curie temperature of 0.3(2) K. No magnetic ordering is observed down to 4.2 K. In accordance with an ionic formula splitting like (Eu{sup II})(Eu{sup III}){sub 2}F{sub 4}S{sub 2} only one third of the europium centers in Eu{sub 3}F{sub 4}S{sub 2} carry permanent magnetic moments. {sup 151}Eu-Moessbauer spectroscopic experiments at 4.2 K show one signal at an isomer shift of -12.4(1) mm/s and a second one at 0.42(4) mm/s. These signals occur in a ratio of 1:2 and correspond to Eu{sup 2+} and Eu{sup 3+}, respectively. The spectra at 78 and 298 K are similar, thus no change in the Eu{sup 2+}/Eu{sup 3+} fraction can be detected. - Graphical abstract: Crystal structure and {sup 151}Eu-Moessbauer spectra of mixed-valent Eu{sub 3}F{sub 4}S{sub 2}.« less

Authors:
;  [1];  [2];  [2]; ;  [3];  [1]
  1. Institut fuer Anorganische Chemie, Universitaet Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart (Germany)
  2. Institut fuer Anorganische und Analytische Chemie, Westfaelische Wilhelms-Universitaet Muenster, Corrensstrasse 30, 48149 Muenster (Germany)
  3. Institut fuer Physikalische Chemie, Westfaelische Wilhelms-Universitaet Muenster, Corrensstrasse 30, 48149 Muenster (Germany)
Publication Date:
OSTI Identifier:
21372388
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 182; Journal Issue: 11; Other Information: DOI: 10.1016/j.jssc.2009.08.023; PII: S0022-4596(09)00408-3; Copyright (c) 2009 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANIONS; CATIONS; CURIE POINT; EUROPIUM FLUORIDES; EUROPIUM IONS; EUROPIUM SULFIDES; FLUORINE IONS; MAGNETIC MOMENTS; MAGNETIC SUSCEPTIBILITY; MOESSBAUER EFFECT; MONOCRYSTALS; PARAMAGNETISM; PLATINUM; SODIUM CHLORIDES; SULFUR IONS; TEMPERATURE RANGE 0000-0013 K; TEMPERATURE RANGE 0065-0273 K; TEMPERATURE RANGE 0273-0400 K; TETRAGONAL LATTICES; ALKALI METAL COMPOUNDS; CHALCOGENIDES; CHARGED PARTICLES; CHLORIDES; CHLORINE COMPOUNDS; CRYSTAL LATTICES; CRYSTAL STRUCTURE; CRYSTALS; ELEMENTS; EUROPIUM COMPOUNDS; FLUORIDES; FLUORINE COMPOUNDS; HALIDES; HALOGEN COMPOUNDS; IONS; MAGNETIC PROPERTIES; MAGNETISM; METALS; PHYSICAL PROPERTIES; PLATINUM METALS; RARE EARTH COMPOUNDS; SODIUM COMPOUNDS; SULFIDES; SULFUR COMPOUNDS; TEMPERATURE RANGE; THERMODYNAMIC PROPERTIES; TRANSITION ELEMENTS; TRANSITION TEMPERATURE

Citation Formats

Grossholz, Hagen, Hartenbach, Ingo, Kotzyba, Gunter, Poettgen, Rainer, E-mail: pottgen@uni-muenster.d, Trill, Henning, Mosel, Bernd D., and Schleid, Thomas, E-mail: schleid@iac.uni-stuttgart.d. Eu{sub 3}F{sub 4}S{sub 2}: Synthesis, crystal structure, and magnetic properties of the mixed-valent europium(II,III) fluoride sulfide EuF{sub 2}.(EuFS){sub 2}. United States: N. p., 2009. Web. doi:10.1016/j.jssc.2009.08.023.
Grossholz, Hagen, Hartenbach, Ingo, Kotzyba, Gunter, Poettgen, Rainer, E-mail: pottgen@uni-muenster.d, Trill, Henning, Mosel, Bernd D., & Schleid, Thomas, E-mail: schleid@iac.uni-stuttgart.d. Eu{sub 3}F{sub 4}S{sub 2}: Synthesis, crystal structure, and magnetic properties of the mixed-valent europium(II,III) fluoride sulfide EuF{sub 2}.(EuFS){sub 2}. United States. doi:10.1016/j.jssc.2009.08.023.
Grossholz, Hagen, Hartenbach, Ingo, Kotzyba, Gunter, Poettgen, Rainer, E-mail: pottgen@uni-muenster.d, Trill, Henning, Mosel, Bernd D., and Schleid, Thomas, E-mail: schleid@iac.uni-stuttgart.d. Sun . "Eu{sub 3}F{sub 4}S{sub 2}: Synthesis, crystal structure, and magnetic properties of the mixed-valent europium(II,III) fluoride sulfide EuF{sub 2}.(EuFS){sub 2}". United States. doi:10.1016/j.jssc.2009.08.023.
@article{osti_21372388,
title = {Eu{sub 3}F{sub 4}S{sub 2}: Synthesis, crystal structure, and magnetic properties of the mixed-valent europium(II,III) fluoride sulfide EuF{sub 2}.(EuFS){sub 2}},
author = {Grossholz, Hagen and Hartenbach, Ingo and Kotzyba, Gunter and Poettgen, Rainer, E-mail: pottgen@uni-muenster.d and Trill, Henning and Mosel, Bernd D. and Schleid, Thomas, E-mail: schleid@iac.uni-stuttgart.d},
abstractNote = {Using the method to synthesize rare-earth metal(III) fluoride sulfides MFS (M=Y, La, Ce-Lu), in some cases we were able to obtain mixed-valent compounds such as Yb{sub 3}F{sub 4}S{sub 2} instead. With Eu{sub 3}F{sub 4}S{sub 2} another isotypic representative has now been synthesized. Eu{sub 3}F{sub 4}S{sub 2} (tetragonal, I4/mmm, a=400.34(2), c=1928.17(9) pm, Z=2) is obtained from the reaction of metallic europium, elemental sulfur, and europium trifluoride in a molar ratio of 5:6:4 within seven days at 850 deg. C in silica-jacketed gas-tightly sealed platinum ampoules. The single-phase product consists of black plate-shaped single crystals with a square cross section, which can be obtained from a flux using equimolar amounts of NaCl as fluxing agent. The crystal structure is best described as an intergrowth structure, in which one layer of CaF{sub 2}-type EuF{sub 2} is followed by two layers of PbFCl-type EuFS when sheeted parallel to the (001) plane. Accordingly there are two chemically and crystallographically different europium cations present. One of them (Eu{sup 2+}) is coordinated by eight fluoride anions in a cubic fashion, the other one (Eu{sup 3+}) exhibits a monocapped square antiprismatic coordination sphere with four F{sup -} and five S{sup 2-} anions. Although the structural ordering of the different charged europium cations is plausible, a certain amount of charge delocalization with some polaron activity has to take place, which is suggested by the black color of the title compound. Temperature dependent magnetic susceptibility measurements of Eu{sub 3}F{sub 4}S{sub 2} show Curie-Weiss behavior with an experimental magnetic moment of 8.19(5) mu{sub B} per formula unit and a paramagnetic Curie temperature of 0.3(2) K. No magnetic ordering is observed down to 4.2 K. In accordance with an ionic formula splitting like (Eu{sup II})(Eu{sup III}){sub 2}F{sub 4}S{sub 2} only one third of the europium centers in Eu{sub 3}F{sub 4}S{sub 2} carry permanent magnetic moments. {sup 151}Eu-Moessbauer spectroscopic experiments at 4.2 K show one signal at an isomer shift of -12.4(1) mm/s and a second one at 0.42(4) mm/s. These signals occur in a ratio of 1:2 and correspond to Eu{sup 2+} and Eu{sup 3+}, respectively. The spectra at 78 and 298 K are similar, thus no change in the Eu{sup 2+}/Eu{sup 3+} fraction can be detected. - Graphical abstract: Crystal structure and {sup 151}Eu-Moessbauer spectra of mixed-valent Eu{sub 3}F{sub 4}S{sub 2}.},
doi = {10.1016/j.jssc.2009.08.023},
journal = {Journal of Solid State Chemistry},
number = 11,
volume = 182,
place = {United States},
year = {Sun Nov 15 00:00:00 EST 2009},
month = {Sun Nov 15 00:00:00 EST 2009}
}
  • La{sub 3}Fe{sub 2-{delta}}S{sub 7} (delta=0.042(6)) was synthesized through a reaction of the elements in a LiCl/KCl flux at 970 K, and its structure was determined by single-crystal X-ray diffraction. The compound crystallizes in the polar hexagonal space group P6{sub 3} with a=10.1906(6), c=5.9543(4) A and Z=2, and adopts the Ce{sub 6}Al{sub 10/3}S{sub 14} structure type. The structure contains both octahedral and tetrahedral iron sites: one-dimensional rods of face-sharing FeS{sub 6} octahedra run along the 6{sub 3} screw axis of the cell; FeS{sub 4} tetrahedra, all pointing in the same direction, are stacked along the threefold rotation axes. The iron-centered polyhedramore » are linked by lanthanum atoms, which are coordinated by [7+1] sulfur atoms in a bicapped trigonal prismatic arrangement. {sup 57}Fe Moessbauer spectroscopy confirms that Fe{sup III} and Fe{sup II} cations occupy the tetrahedral and octahedral iron sites, respectively. Magnetic susceptibility data indicate an antiferromagnetic transition at T{sub N}{approx}155 K. Density functional band structure calculations within the local density approximation reveal two covalent Fe-S subsystems within the compound that mix only weakly. A large anisotropy is indicated by bands that disperse predominantly along the hexagonal axis. The electronic band structure suggests pseudo-one-dimensional metallic conductivity along the rods of face-sharing FeS{sub 6} octahedra. However, due to the defects on the Fe{sup II} positions, La{sub 3}Fe{sub 2-{delta}}S{sub 7} shows an activated conducting behavior. - Graphical Abstract: Rods of face-sharing [Fe{sup II}S{sub 6}]-octahedra and [Fe{sup III}S{sub 4}]-tetrahedra, all pointing in the same direction, dominate the polar structure. Vacancies in the octahedral Fe positions downgrade one-dimensional metallic conductivity to an activated semi-conducting behavior.« less
  • The [M{sub x}{sup II}M{sub 2.5-x}{sup III}(H{sub 2}O){sub 2}(HP{sup III}O{sub 3}){sub y}(P{sup V}O{sub 4}){sub 2-y}F; M=Fe (1), x=2.08, y=1.58; M=Co (2), x=2.5, y=2; Ni (3), x=2.5, y=2] compounds have been synthesized using mild hydrothermal conditions at 170 deg. C during five days. Single-crystals of (1) and (2), and polycrystalline sample of (3) were obtained. These isostructural compounds crystallize in the orthorhombic system, space group Aba2, with a=9.9598(2), b=18.8149(4) and c=8.5751(2) A for (1), a=9.9142(7), b=18.570(1) and c=8.4920(5) A for (2) and a=9.8038(2), b=18.2453(2) and c=8.4106(1) A for (3), with Z=8 in the three phases. An X-ray diffraction study reveals that themore » crystal structure is composed of a three-dimensional skeleton formed by [MO{sub 5}F] and [MO{sub 4}F{sub 2}] (M=Fe, Co and Ni) octahedra and [HPO{sub 3}] tetrahedra, partially substituted by [PO{sub 4}] tetrahedra in phase (1). The IR spectra show the vibrational modes of the water molecules and those of the (HPO{sub 3}){sup 2-} tetrahedral oxoanions. The thermal study indicates that the limit of thermal stability of these phases is 195 deg. C for (1) and 315 deg. C for (2) and (3). The electronic absorption spectroscopy shows the characteristic bands of the Fe(II), Co(II) and Ni(II) high-spin cations in slightly distorted octahedral geometry. Magnetic measurements indicate the existence of global antiferromagnetic interactions between the metallic centers with a ferromagnetic transition in the three compounds at 28, 14 and 21 K for (1), (2) and (3), respectively. Compound (1) exhibits a hysteresis loop with remnant magnetization and coercive field values of 0.72 emu/mol and 880 Oe, respectively. - Abstract: Polyhedral view of the crystal structure of the [M{sub x}{sup II}M{sub 2.5-x}{sup III}(H{sub 2}O){sub 2}(HP{sup III}O{sub 3}){sub y}(P{sup IV}O{sub 4}){sub 2-y}F; M=Fe, x=2.08, y=1.58; M=Co, Ni, x=2.5, y=2] compounds showing the sheets along the [001] direction.« less
  • The complex of composition [Eu(C{sub 5}H{sub 4}NCO{sub 2}){sub 3}Phen(OH{sub 2}){sub 2}OS(CH{sub 3}){sub 2}] was synthesized upon the interaction of tris(nicotinato)aquaeuropium(III) with 1,10-phenanthroline in an alcohol-dimethyl sulfoxide solution. The compound crystallizes in an orthorhombic crystal system; the unit-cell parameters are as follows: a = 15.266(4) {Angstrom}, b = 15.224(4) {Angstrom}, c = 28.381(7) {Angstrom}, V = 6595.9 {Angstrom}{sup 3}, Z = 8, d(calcd.) = 1.572 g/cm{sup 3}, space group Pbca. Five oxygen atoms of the three nicotinate ions, two oxygen atoms of the water molecules, and two nitrogen atoms of the phenanthroline molecule are involved in coordination with the Eu{sup 3+}more » cation. The oxygen atom of dimethyl sulfoxide does not participate in the coordination but forms a hydrogen bond with one of the coordinated water molecules.« less
  • Here, a new compound, Eu 3Ir 2In 15 has been synthesized using indium as an active metal flux. The compound crystallizes in tetragonal P4/mbm space group with lattice parameters, a = 14.8580(4) Å, b = 14.8580(4) Å, c = 4.3901(2) Å. It was further characterized by SEM-EDX studies. The temperature dependent magnetic susceptibility suggests that Eu in this compound is exclusively in divalent state. The effective magnetic moment (μ eff) of this compound is 7.35 μ B/Eu ion with paramagnetic Curie temperature (θ p) of -28 K suggesting antiferromagnetic interaction. The mixed valent nature of Eu observed in magnetic measurementsmore » was confirmed by XANES measurements. The compound undergoes demagnetization at a low magnetic field (10 Oe), which is quite unusual for Eu based intermetallic compounds. Temperature dependent resistivity studies reveal that the compound is metallic in nature. A comparative study was made between Eu 3Ir 2In 15 and hypothetical vacancy variant Eu 5Ir 4In 10 which also crystallizes in the same crystal structure However our computational studies along with control experiments suggest that the latter is thermodynamically less feasible compared to the former and hence we proposed that it is highly unlikely that a RE 5T 4X 10 would exist with X as a group 13 elements.« less
  • One new manganese thiogermanate, [(dien){sub 2}Mn]Ge{sub 2}S{sub 4} (dien=diethylenetriamine), was prepared under mild solvothermal conditions and structurally and spectroscopically characterized. The title compound crystallizes in the orthorhombic system, chiral space group P2{sub 1}2{sub 1}2{sub 1} (no. 19) with a=9.113(4) Å, b=12.475(5) Å, c=17.077(7) Å, V=1941.5(15) Å{sup 3} and Z=4. Its structure features a three-dimensional (3D) network composed of a one-dimensional (1D) [Ge{sub 2}S{sub 4}]{sup 2−} anionic chain and a [(dien){sub 2}Mn]{sup 2+} complex interconnected via various hydrogen bonds. The most interesting structural feature of the compound is the presence of two different oxidation states of germanium centers in the 1Dmore » [Ge{sub 2}S{sub 4}]{sup 2−} chain, which is also supported by the result of X-ray photoelectron spectroscopy measurement. The optical property of the title compound has also been studied by UV–vis spectra. - Graphical abstract: One new thiogermanate, [(dien){sub 2}Mn]Ge{sub 2}S{sub 4}, contains a one-dimensional [Ge{sub 2}S{sub 4}]{sup 2−} anionic chain with two different oxidation states of germanium centers. Display Omitted - Highlights: • One new manganese thiogermanate [(dien){sub 2}Mn]Ge{sub 2}S{sub 4} was prepared. • The compound features 1D [Ge{sub 2}S{sub 4}]{sup 2−} chain composed of [Ge{sup II}S{sub 4}] and [Ge{sup IV}S{sub 4}] tetrahedra. • The first example of inorganic–organic hybrid thiogermanates with mixed valent Ge centers.« less