Ternary Rhodium Borides A3Rh5B2 (A = Mg,Sc) and Quaternary Derivatives A2MRh5B2. Preparation,Crystal Structure (M = Main Group and 3 d Elements), and Magnetism (M = Mn,Fe)

The new ternary rhodium borides Mg₃Rh₅B₂ and Sc₃Rh₅B₂ (P4/mbm, Z = 2; a = 943.4(1) pm, c = 292.2(1) pm and a = 943.2(1) pm, c = 308.7(1) pm, respectively) crystallize with the Ti₃Co₅B₂ type structure. Mg and Sc may in part be substituted by a variety of elements M. For M = Si and Fe, homogeneity ranges were found according to A_3–xM_xRh₅B₂ with 0 ≤ x ≤ 1.0 for A = Sc and with x up to 1.5 for A = Mg. Quaternary compounds with x = 1 (A₂MRh₅B₂: A/M in short) were prepared with M = Be, Al, Si, P, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Sn (Co, Ni only with A = Mg; Sn only with A = Sc; P, As with deficiencies). Single crystal X‐ray investigations show an ordered substitutional variant of the Ti₃Co₅B₂ type in which the M atoms are arranged in chains along [001] with intrachain and interchain M–M distances of about 300 pm and 660 pm, respectively. Measuring the magnetisation (1.7 K–800 K) of the phases Mg/Mn, Sc/Mn, Mg/Fe, and Sc/Fe reveals antiferromagnetic interactions in the first and dominating ferromagnetic intrachain interactions in the remaining ones. Interchain interactions of antiferromagnetic nature are evident in Sc/Mn and Mg/Fe leading to metamagnetism below T_N = 130 K, while Sc/Fe behaves ferromagnetically below T_C = 450 K. The overall trend towards stronger ferromagnetic interactions with increasing valence electron concentration is obvious.     

Komplexboride in den Systemen Hf−Mo−B und Hf−W−B

Zusammenfassung In den Dreistoffen: Hf–{Mo, W}–B werden ternäre Boride Hf₉Mo₃B_2-x und (Hf, W)₁₂B_2-x aufgefunden und strukturell charakterisiert. Gitterparameter und Atomparameter der K (Kappa)-Carbid-ähnlichen Phasen werden bestimmt. Die Schmelzgleichgewichte im System Hf–Mo–B werden fast vollständig ermittelt. Hafnium läßt sich in Hf₉Mo₃B_2-x etwa zur Hälfte durch Zirkonium ersetzen.

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Complex borides in the systems hafnium —(molybdenum, tungsten)—boron

Complex borides of formula Hf₉Mo₃B_2-x and (Hf, W)₁₂B_2-x have been detected within the ternary systems: Hf–{Mo, W}–B. The lattice and atomic parameters of the K (Kappa) carbide like phases have been determined. Most of the reaction equilibria of the ternary system: Hf–Mo–B have been derived. Hafnium can be substituted by zirconium within Hf₉Mo₃B_2-x up to (Hf_0.5Zr_0.5)₉Mo₃B_2-x .

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Ferro- and antiferromagnetism in oxychalcogenides LnCrOX2 (Ln = La or Nd and X = S or Se)

The two isomorphous compounds LaCrOS₂ and LaCrOSe₂ are ferromagnetic (T_c = 35 and 51 K, respectively). This implies ferromagnetic super-superexchange interactions. NdCrOS₂ is antiferromagnetic (T_N = 72 K) and undergoes a spin-flop transition (H_c = 54 KOe at 20 K). The study of the thermal variation of Cr³⁺ and Nd³⁺ magnetic moments below T_N allows a rough estimate of the Cr---Nd and Cr---Cr exchange fields ratio (0.1).     

Phasen mit oktaedrischen Bauelementen des Übergangsmetalls

Zusammenfassung Legierungen in den Systemen: {Zr, Hf, V, Nb, Ta}-{Ni, Cu, Ag, Au}-{Zn, Al, Ga, Sn, Pb} werden aus den Komponenten vorzugsweise im Verhältnis 50–60 At%T-, 10–30 At% 8a-und 1b-Metall und 15–40 At% 2b–4b-Metall hergestellt. Die Phasen Zr₃Cu₂Zn, Zr₃Ag₂Zn, Zr₃Au₂Al, Hf₃Cu₂Zn, Hf₃Au₂Al kristallisieren im Ti₂Ni-Typ bzw. in einer Variante desselben. Hf₅Sn₄ ist mit Ti₅Ga₄ isotyp, dagegen lassen sich homogene Legierungen mit fast gleicher Struktur wie Zr₅Pb₃Cu, Hf₅Sn₃Ni, Hf₅Sn₃Cu und Hf₅Pb₃Cu ebensogut zum aufgefüllten Mn₅Si₃-Typ zählen. Die kleinen Ni- und Cu-Atome übernehmen dabei die Rolle von Nichtmetallen. V₃(Au,Ga)₂Nx, Nb₃(Au,Ga)₂Nx und Ta₃(Au,Ga)₂Nx besitzen ein metallisches Wirtgitter vom -Mangan-Typ; bei Nb₃Au₂ scheint die Anwesenheit von Stickstoff (Sauerstoff) zur Stabilisierung des -Mn-Carbid-Typs erforderlich. Die in der Literatur¹ angegebene Phase Nb₅₅Au₄₅ mit -Mn-Typ konnte in stickstoff-freien (binären) Legierungen nicht erhalten werden.

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Alloys within the ternary systems: {Zr, Hf, V, Nb, Ta}-{Ni, Cu, Ag, Au}-{Zn, Al, Ga, Sn, Pb} have been prepared mainly in the domain of 50–60 a/oT, 10–30 a/o 8a- and 1b-metal and 15–40 a/o 2b–4b-metal. The phases Zr₃Cu₂Zn, Zr₃Ag₂Zn, Zr₃Au₂Al, Hf₃Cu₂Zn, Hf₃Au₂Al are found to be isostructural with the Ti₂Ni-type. Hf₅Sn₄ crystallizes with Ti₅Ga₄-type, while homogenous samples having almost the same crystal structure such as Zr₅Pb₃Cu, Hf₅Sn₃Ni, Hf₅Sn₃Cu and Hf₅Pb₃Cu can also be considered as a filled Mn₅Si₃-structure. The small Ni- and Cu-atoms do play the same role as non metal atoms. V₃(Au, Ga)₂Nx, Nb₃(Au, Ga)₂Nx and Ta₃(Au, Ga)₂Nx possess a partially ordered parent lattice of the -manganese-type.It appears however that for stabilization of Nb₃Au₂ non metals, such as oxygen, nitrogen or carbon have to be present. The phase of formula Nb₅₅Au₄₅ having -Mn-structure reported in the literature cannot be observed in purely binary Nb-Au-alloys.

     

Über den aufgefüllten Re3B-Typ in den Systemen (Zr,Hf)−(Fe,Co, Ni)−O

Zusammenfassung Es wird gezeigt, daß die Oktaederlücken des Re₃B-Typs in obigen Systemen teilweise durch Sauerstoff aufgefüllt werden. Die Auffüllungsbereichex der Phasen Zr₃CoO _x , Zr₃NiO _x , Hf₃CoO _x und Hf₃NiO _x werden studiert.

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On the filled upRe ₃ B-type in the systems(Zr, Hf)–(Fe, Co, Ni)–O

It is shown that the octahedral voids of the Re₃B-type are partially filled up by oxygen in the above systems. The homogenous ranges ofx of the phases Zr₃CoO _x , Zr₃NiO _x , Hf₃CoO _x , and Hf₃NiO _x are studied.

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Kristallchemische Untersuchungen in Systemen mitT-Elementen, (Cu,Ag) und (Al,Ga)

Zusammenfassung In den Dreistoffen: Ti{Zr, Hf, Nb}–(Cu, Ag)–(Al, Ga) werden aus den Komponenten im Bereich von 50 At%T, 20–40 At% (Cu, Ag) und 10–30 At% (Al, Ga) Legierungen hergestellt und röntgenographisch untersucht. Es werden ternäre Phasen mit der ungefähren Zusammensetzung Ti(Cu, Al)₂, Zr₃Cu₂Al, Zr₃Ag₂Al, Hf₃Cu₂Al, Hf₃Ag₂Al und Nb₃Cu₂Ga aufgefunden. Die erstgenannte Kristallart gehört zum MgZn₂-Typ, während die übrigen mit der E 9₃-Struktur isotyp sind. Die Phasen mit E 9₃-Typ können geringe Mengen an Nichtmetall (N, O) enthalten.

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The ternary compounds Ti(Cu, Al)₂, Zr₃Cu₂Al, Zr₃Ag₂Al, Hf₃Cu₂Al, Hf₃Ag₂Al and Nb₃Cu₂Ga have been prepared and examined. It has been shown that Ti(Cu, Al)₂ possesses the MgZn₂ structure, while the other compounds crystallize in the E 9₃-type. The latter phases presumably contain a small amount of non-metals (N, O).

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T = Übergangsmetall.     

Scandium as an Element Intermediate between Rare Earth and Transition Metals in Intermetallics: Crystal Structures of Sc2Fe12P7, Sc3.6Fe10.4P7, and Sc2Co4P3. Other New Compounds with Zr2Fe12P7, Hf2Co4P3, Sc5Co19P12, and Yb6Co30P19 Type Structures

Abstract. Twenty five ternary phosphides crystallizing with four different but closely related structure types were prepared using elemental tin as a flux. Their lattice constants are reported. New compounds include Sc₂Fe₁₂P₇, Sc_3.6Fe_10.4P₇, Y₂Co₁₂P₇, and Hf₂T₁₂P₇ with T = Fe, Co, Ni. They crystallize with the hexagonal Zr₂Fe₁₂P₇ type structure, which was refined from single‐crystal X‐ray data of Sc_3.6Fe_10.4P₇: a = 944.1(1) pm, c = 363.4(1) pm, R = 0.041 for 719 unique structure factors and 23 variable parameters. The excess scandium atoms occupy one of the four iron sites of the Zr₂Fe₁₂P₇ type structure which has a higher coordination number than the other three iron sites. The two isotypic phosphides Sc₂Fe₁₂P₇ and Sc_3.6Fe_10.4P₇ do not form a continuous series of solid solutions. The new compounds Sc₂Co₄P₃ and Sc₂Ni₄P₃ are isotypic with Hf₂Co₄P₃. This hexagonal structure was refined for Sc₂Co₄P₃ from single crystal data: a = 1211.5(2) pm, c = 363.7(1) pm, R = 0.025 for 500 F_o and 38 variables. Other new compounds reported are Sc₅Ni₁₉P₁₂, Zr₅Fe₁₉P₁₂, Hf₅Fe₁₉P₁₂, and Hf₅Co₁₉P₁₂ which crystallize with Sc₅Co₁₉P₁₂ type structure, and the Yb₆Co₃₀P₁₉ type phosphides Sc₆Co₃₀P₁₉, Zr₆Co₃₀P₁₉, and Hf₆Co₃₀P₁₉. The structural relationships of these ternary phosphides are discussed with special attention to the environments of the transition metal atoms.     

Geometry,stability, and isomerization of BnN2 (n = 1−6) isomers

We perform a systematic study on the geometry, stability, nature of bonding, and potential energy surface of low‐lying isomers of planar and cyclic B_nN₂ (n = 1?6) at the CCSD(T)/6‐311+G(d)//B3LYP/6‐311+G(d) level. B_nN₂ (n = 2?4) clusters are structurally similar to pure boron clusters. The evolution of the binding energy per atom, incremental binding energy, and second‐order difference of total energy with the size of B_nN₂ reveals that the lowest energy isomer of B₃N₂ has high stability. B₅N₂ and B₆N₂ possess π‐aromaticity according to Hückel (4n + 2) rule. The aromaticity of some isomers of B₄N₂ and B₆N₂ is examined based on their valence molecular orbitals. At the CCSD(T)/6‐311+G(d)//B3LYP/6‐311+G(d) level, several B₂N₂, B₃N₂, B₄N₂, and B₅N₂ isomers are predicted to be stable both thermodynamically and kinetically, and detectable in future experiments. © 2013 Wiley Periodicals, Inc.     

Structure, bonding, and magnetic response in two complex borides: Zr2Fe1−δRu5+δB2 and Zr2Fe1−δ(Ru1−xRhx)5+δB2

Polycrystalline samples of two complex intermetallic borides Zr₂Fe_1−δRu_5+δB₂ and Zr₂Fe_1−δ(Ru_1−xRh_x)_5+δB₂ (δ=ca. 0.10; x=0.20) were synthesized by high-temperature methods and characterized by single-crystal X-ray diffraction, energy dispersive spectroscopy, and magnetization measurements. Both structures are variants of Sc₂Fe(Ru_1−xRh_x)₅B₂ and crystallize in the space group P4/mbm (no. 127) with the Ti₃Co₅B₂-type structure. These structures contain single-atom, Fe-rich Fe/Ru or Fe/Ru/Rh chains along the c-axis with an interatomic metal-metal distance of 3.078(1) Å, a feature which makes them viable for possible low-dimensional temperature-dependent magnetic behavior. Magnetization measurements indicated weak ferrimagnetic ordering with ordering temperatures ca. 230 K for both specimens. Tight-binding electronic structure calculations on a model “Zr₂FeRu₅B₂” using LDA yielded a narrow peak at the Fermi level assigned to Fe-Fe antibonding interactions along the c-axis, a result that indicates an electronic instability toward ferromagnetic coupling along these chains. Spin-polarized calculations of various magnetic models were examined to identify possible magnetic ordering within and between the single-atom, Fe-rich chains.     

Hydrides of intermetallic compounds with a H/M ratio greater than unity obtained at high hydrogen pressures

Novel hydride phases with H/M > 1 based on Zr₂Pd, Hf₂Pd, and Hf₂Cu (structures of the MoSi₂, type) have been synthesized at high H₂ pressures. The X-ray diffraction investigations of the resulting hydrides have been carried out. Some factors determining the maximum hydrogen content in the hydrides of intermetallic compounds are discussed. A model structure of the hydrides obtained is proposed, which assumes the possibility of direct H-H interactions when the interatomic distances are less than 1 Å.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 843–845, May, 1993.     

Magnetische Messungen in den Systemen (Zr,Hf)—(Fe,Co,Ni)—O

The phases Zr₃Fe, Zr₃CoO _x (x=0,35;1);Zr₃NiO _x (x=0,2; 1); Hf₃NiO are measured magnetically in the range between 1300°K and 90°K. Whereas Zr₃Fe is ferromagnetic, the other isotypical structures are paramagnetic.

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Ternary Transition Metal Antimonides T5T' 1‐xSb2+x (T = Ti,Zr, Hf; T' = Fe,Co, Ni,Cu, Ru,Rh, Pd,Cd) with Nb5SiSn2 (Ordered W5Si3, Filled V4SiSb2) Type Structure

Fifteen new ternary antimonides T₅T' _1‐xSb_2+x were synthesized by reaction of the elemental components in an arc‐melting furnace. They crystallize with a tetragonal structure first reported for Nb₅SiSn₂ (space group I4/mcm, Z = 4.) A structure refinement from four‐circle X‐ray diffractometer data of Hf₅Fe_1‐xSb_2+x (a = 1086.0(1) pm, c = 550.1(1) pm, R = 0.033 for 270 structure factors and 18 variable parameters) showed deviations from the ideal occupancy for two atomic sites, resulting in the composition Hf_4.929(3)Fe_0.67(1)Sb_2.33(1). Structure refinements from X‐ray powder data resulted in the formula Ti₅Ni_0.45(2)Sb_2.55(2), while no deviation from the ideal composition was observed for Ti₅RhSb₂. The crystal structures of these compounds are discussed together with those of related binary and ternary compounds.     

Slater-Pauling behavior within quaternary intermetallic borides of the Ti3Co5B2 structure-type

First-principles, density-functional studies of several intermetallic borides of the general type M₂M′Ru_5−nRh_nB₂ (n=0-5; M=Sc, Ti, Nb; M′=Fe, Co) show that the variation in saturation magnetic moment with valence-electron count follows a Slater-Pauling curve, with a maximum moment occurring typically at 66 valence electrons. The magnetic moments in these compounds occur primarily from the 3d electrons of the magnetically active M′ sites, with some contribution from the Ru/Rh sites via magnetic polarization. Electronic DOS curves reveal that a rigid-band approach is a reasonable approximation for the estimation of saturation moments and the analysis of orbital interactions in this family of complex borides. COHP analyses of the M′−M′ orbital interactions indicate optimized interactions in the minority spin states for Co-containing phases, but strong bonding interactions remaining in Fe-containing phases.     

Magnetic order and valence fluctuation in a Pu?Ga intermetallic compound studied via a first principles calculation

In order to reveal electronic properties of a plutonium-gallium intermetallic compound (Pu₃Ga), and its potential implication for microscopic mechanisms for effects of Ga doping on the electronic and structural properties, as well as the phase stability of delta-phase Pu Ga alloy, a first principles calculation on the magnetic properties of this system is implemented by using density functional theory (DFT) plus on-site Coulomb repulsion U with nonmagnetic, ferromagnetic, and antiferromagnetic (AFM) orders, while the intermediate correlation effect, which is beyond the scope of pure itinerant and localized electronic model, is investigated by using a many-body technique combining DFT and dynamical mean-field theory considering the dynamical correlation effect due to the incompletely filled Pu 5f orbitals and the relativistic effect by inclusion of spin-orbit coupling (SOC). Our findings show that Pu₃Ga is a bad metal with AFM order, which is in good agreement with the experimental magnetic measurement. SOC further splitting Pu 5f states into j = 5/2 and j = 7/2 manifolds, the former exhibits metallic character, while the latter insulating feature. Occupation analysis establishes that an average occupancy of Pu 5f electrons in Pu₃Ga is n_f = 4.9598, this result together with the spectrum function indicates that 5f electrons in this system might be a localized state with strong valence fluctuation. Additionally, optimization of lattice parameter, density of state, and momentum-resolved electronic spectrum function are also presented.     

Chemical bonding in EuTGe (T=Ni, Pd, Pt) and physical properties of EuPdGe

EuPdGe was prepared from the elements by reaction in a sealed tantalum tube in a high-frequency furnace. Magnetic susceptibility measurements show Curie-Weiss behavior above 60 K with an experimental magnetic moment of 8.0(1)μ_B/Eu indicating divalent europium. At low external fields antiferromagnetic ordering is observed at T_N=8.5(5) K. Magnetization measurements indicate a metamagnetic transition at a critical field of 1.5(2) T and a saturation magnetization of 6.4(1)μ_B/Eu at 5 K and 5.5 T. EuPdGe is a metallic conductor with a room-temperature value of 5000±500 μΩ cm for the specific resistivity. ¹⁵¹Eu Mössbauer spectroscopic experiments show a single europium site with an isomer shift of δ=−9.7(1) mm/s at 78 K. At 4.2 K full magnetic hyperfine field splitting with a hyperfine field of B=20.7(5) T is observed. Density functional calculations show the similarity of the electronic structures of EuPdGe and EuPtGe. T-Ge interactions (T=Pd, Pt) exist in both compounds. An ionic formula splitting Eu²⁺T⁰Ge²⁻ seems more appropriate than Eu²⁺T²⁺Ge⁴⁻ accounting for the bonding in both compounds. Geometry optimizations of EuTGe (T=Ni, Pt, Pd) show weak energy differences between the two structural types.     

Die Kristallstruktur von Zr2Al und Hf2Al

Zusammenfassung Im Zweistoff: Zr–Al bzw. Hf–Al werden zwei neue Kristallarten Zr₂Al und Hf₂Al mit CuAl₂-Struktur nachgewiesen; die Parameter sind:a=6,840 bzw. 6,76₂ undc=5,49₀ bzw. 5,37₄ kX·E. In den Dreistoffen: Zr–Al–Si und Hf–Al–Si besteht jeweils ein lückenloser Übergang zwischen den isotypen Phasen Zr₂Al und Zr₂Si bzw. Hf₂Al und Hf₂Si.     

A density‐functional theory approach to the separation of K2ZrF6 and K2HfF6 via fractional crystallization

Because of the low absorption cross‐section for thermal neutrons of zirconium (Zr) as opposed to hafnium (Hf), Zr‐metal must essentially be Hf‐free (<100 ppm Hf) to be suitable for use in nuclear reactors. However, Zr and Hf always occur together in nature, and due to very similar chemical and physical properties, their separation is particularly difficult. Separation can be achieved by traditional liquid–liquid extraction or extractive distillation processes, using Zr(Hf)Cl₄ as feedstock. However, the production of K₂Zr(Hf)F₆ via the plasma dissociation route, developed by the South African Nuclear Energy Corporation Limited (Necsa), could facilitate the development of an alternative separation process. In this theoretical study, the results of density‐functional theory (DFT) simulations of K₂Zr_(1‐z)Hf_zF₆ solid solutions [using Cambridge Serial Total Energy Package (CASTEP)] are presented, for which the supercell approach was applied in an attempt to determine whether solid solution formation during crystallization from aqueous solutions (fractional crystallization) is thermodynamically possible, which would hinder the separation efficiency of this method. Consequently, the calculated thermodynamic properties of mixing were used to evaluate the separation efficiency of Zr and Hf by fractional crystallization using a thermodynamic model to calculate the relative distribution coefficients. The small mixing enthalpies that were calculated from the DFT results, indicates that lattice substitution of Zr(IV) by Hf(IV) in K₂ZrF₆ could occur with relative ease. This is not surprising, considering the close similarities between Zr and Hf, and it was therefore concluded that K₂Zr_(1‐z)Hf_zF₆ solid solution formation might well restrict the separation efficiency of Zr and Hf by fractional crystallization of K₂Zr(Hf)F₆. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2011     

Magnetic and thermodynamic properties of NdT2Ge2 (T=Pd, Ag) compounds

Physical properties of NdPd₂Ge₂ and NdAg₂Ge₂, crystallizing with the tetragonal ThCr₂Si₂-type crystal structure, were investigated by means of magnetic, calorimetric, electrical transport as well as by neutron diffraction measurements. The specific heat studies and neutron diffraction measurements were performed down to 0.30 K and 0.47 K, respectively. Both compounds exhibit antiferromagnetic ordering below T_N equal to 1.5 K for NdPd₂Ge₂ and 1.8 K for NdAg₂Ge₂. Neutron diffraction data for the latter germanide indicate antiferromagnetic collinear structure described by the propagation vector k=(0.5, 0, 0.5). The Nd magnetic moments equal to 2.24(5) μ_B at 0.47 K are aligned along the a-axis and have the +− sequence within the crystal unit cell. For NdPd₂Ge₂ only very small Bragg peaks of magnetic origin were observed in the neutron diffraction patterns measured below T_N, thus hampering determination of the magnetic structure. Both compounds exhibit metallic-like electrical conduction. From the specific heat data the crystal electric field (CEF) levels schemes were determined. Difference between the overall CEF splitting in the two compounds is correlated with their structural parameters.     

Synthesis, crystal structure and characterization of iron pyroborate (Fe2B2O5) single crystals

Single crystals of iron(II) pyroborate, Fe₂B₂O₅, were prepared at 1000–1050 °C under an argon atmosphere. The crystals were transparent, yellowish in color and needle-like or columnar. The crystal structure of Fe₂B₂O₅ was analyzed by single-crystal X-ray diffraction. Refined triclinic unit cell parameters were a=3.2388(2), b=6.1684(5), c=9.3866(8) Å, α=104.613(3)°, β=90.799(2)° and γ=91.731(2)°. The final reliability factors of refinement were R1=0.020 and wR2=0.059 [I > 2σ(I)]. Transmittance over 50% in the visible light region from 500 to 750 nm was observed for a single crystal of Fe₂B₂O₅ with a thickness of about 0.3 mm. The light absorption edge estimated from a diffuse reflectance spectrum was at around 350 nm (3.6 eV). Magnetic susceptibility was measured for single crystals at 4–300 K. Fe₂B₂O₅ showed antiferromagnetic behavior below the Néel temperature, T_N≈70 K, and the Weiss temperature was T_W=36 K. The effective magnetic moment of Fe was 5.3μ_B.     

2D Compound Constructed by Cu3 Units with Mixed Azido and Tetrazole Double Bridges: Synthesis,Structure, and Theoretical Study on Magnetic Properties

The two‐dimensional (2D) layer Cu^II compound [Cu₃(L)₂(N₃)₄] ( 1 ) [L = 2‐amino‐3‐(5‐tetrazole)‐methyate‐N‐pyridine] was synthesized by in‐situ hydrothermal reaction of CuCl₂ · 2H₂O, NaN₃, and 3‐(5‐tetrazole)‐methyate‐N‐pyridine. The central Cu1 and Cu2 atoms are located in five‐coordinate and six‐coordinate arrangements, respectively. Three Cu^II ions are linked by mixed double EO (end‐on)‐azido‐tetrazole bridges to give trinuclear Cu^II clusters, which are further extended by EE (end‐to‐end) azido bridges to form 2D metal‐organic layers. The magnetic exchange interactions in complex 1 were investigated by DFT calculations, and the calculated exchange interaction (J = –849 cm^–1) revealed that the double EO‐azido‐tetrazole bridges transmit antiferromagnetic coupling between Cu^II ions.