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1.
The electronic structures and spectroscopic properties of a series of mixed bis-cyclometalated iridium(III) complexes [Ir(ppy)2X2]− (X = CN, 1; X = NCS, 2; X = NCO, 3; ppy = 2-phenylpyridl) were investigated at the B3LYP/LANL2DZ and CIS/LANL2DZ levels. The calculated geometry parameters in the ground state are well consistent with the corresponding experimental values. The HOMO of 1 is dominantly localized on Ir atom and ppy ligand, but the HOMO of 2 and 3 have significant X ligand composition. Under the TD-DFT level with PCM model, the absorption and phosphorescence in CH2Cl2 media were calculated based on the optimized geometries in the ground and excited states, respectively. The lowest-lying absorption of 1 at 403 nm is attributed to {[dx2-y2(Ir)+dxy(Ir)+π(ppy)]→[π∗(ppy)]} transition with metal-to-ligand and intraligand charge transfer (MLCT/ILCT) transition characters, whereas those of 2 (449 nm) and 3 (475 nm) are related to {[dx2-y2(Ir)+dxy(Ir)+π(ppy)+π(NCS/NCO)]→[π∗(ppy)]} transition with MLCT/ILCT and ligand-to-ligand charge transfer (LLCT) transition characters. The phosphorescence of 1 at 466 nm can be described as originating from 3{[dx2-y2(Ir)+dxy(Ir)+π(ppy)][π∗(ppy)]} excited state, while those of 2 (487 nm) and 3 (516 nm) originate from 3{[dx2-y2(Ir)+dxy(Ir)+π(ppy)+π(NCS/NCO)][π∗(ppy)]} excited states. The calculated results showed that the transition character of the absorption and emission can be changed by adjusting the π electron-accepting abilities of the X ligands and the phosphorescent color can be tuned by altering the X ligands. 相似文献
2.
Andrew J. Hallett 《Journal of organometallic chemistry》2010,695(22):2401-2409
The syntheses of two new ligands and five new heteroleptic cyclometallated Ir(III) complexes are reported. The ligands are based upon a functionalised anthra[1,2-d]imidazole-6,11-dione core giving LH1−3 incorporating a pendant pyridine, quinoline or thiophene unit respectively. Neutrally charged, octahedral complexes [Ir(ppy)2(L1−3)] are chelated by two cyclometallated phenylpyridine (ppy) ligands and a third, ancillary deprotonated ligand L1−3, whilst cationic analogues could only be isolated for [Ir(ppy)2(LH1−2)][PF6]. X-ray crystal structures for [Ir(ppy)2(L1)], [Ir(ppy)2(LH1)][PF6] and [Ir(ppy)2(L2)] showed the complexes adopt a distorted octahedral coordination geometry, with the anthra[1,2-d]imidazole-6,11-dione ligands coordinating in a bidentate fashion. Preliminary DFT calculations revealed that for the complexes of LH1 and LH2 the LUMO is exclusively localized on the ancillary ligand, whereas the nature of the HOMO depends on the protonation state of the ancillary ligand, often being composed of both Ir(III) and phenylpyridine character. UV-vis. and luminescence data showed that the ligands absorb into the visible region ca. 400 nm and emit ca. 560 nm, both of which are attributed to an intra-ligand CT transition within the anthra[1,2-d]imidazole-6,11-dione core. The complexes display absorption bands attributed to overlapping ligand-centred and 1MLCT-type electronic transitions, whilst only [Ir(ppy)2(L2)] appeared to possess typical 3MLCT behaviour (λem = 616 nm; τ = 96 ns in aerated MeCN). The remaining complexes were generally visibly emissive (λem ≈ 560-570 nm; τ < 10 ns in aerated MeCN) with very oxygen-sensitive lifetimes more indicative of ligand-centred processes. 相似文献
3.
Time-dependent density functional theory with quadratic response methodology is used in order to calculate and compare spin–orbit coupling effects and the main mechanism of phosphorescence of the neutral Ir(ppy)3 and cationic [Ir(bpy)3]3+ tris-iridium compounds, [Ir(ppy)2(bpy)]+ and [Ir(2-phenylpyridine)2(4,4′-tert-butyl-2,2′-bipyridine]+ complexes, including also the recently synthesised [Ir(2-phenylpyridine)2(4,4′-dimethylamino-2,2′-bipyridine]+ and [Ir(2,4-difluorophenylpyridine)2(4,4′-dimethylamino-2,2′-bipyridine]+ dyes, where ppy = 2-phenylpyridine and bpy = 2,2′-bipyridine ligands. Comparison with the symmetric, lighter and more studied [Ru(bpy)3]2+ and [Rh(bpy)3]3+ complexes is also presented. Variations in phosphorescence lifetimes for Ir(ppy)3 and [Ir(bpy)3]3+ dyes as well as for the mixed cationic complexes are well reproduced by the quadratic response method. All the ortho-metalated iridium compounds exhibit strong phosphorescence, which is used in organic light-emitting diodes (OLEDs) to overcome the efficiency limit imposed by the formation of triplet excitons. The results from the first principle theoretical analysis of phosphorescence have helped to clarify the connections between the main features of electronic structure and the photo-physical properties of the studied heavy organometallic OLED materials. 相似文献
4.
Yiu-Keung Sau 《Journal of organometallic chemistry》2010,695(9):1399-6514
Treatment of [Cp∗Ir(ppy)Cl] (Cp∗ = η5-C5Me5, ppyH = 2-(2-pyridyl)phenyl) with Ag(OTf) (OTf− = triflate) in MeOH and MeCN gave the solvento complexes [Cp∗Ir(ppy)(solv)][OTf] (solv = MeOH (1) and MeCN (2)). Complex 1 is capable of catalyzing oxidation and azirdination of styrene with PhIO and PhINTs (Ts = tosyl), respectively. Treatment of 2 with a stoichiometric amount of PhINTs resulted in the insertion of the NTs group into the Ir-C(ppy) bond and formation of [Cp∗Ir(η2-ppy-NTs)(MeCN)][OTf] (3). Treatment of 1 with R2E2 afforded [Cp∗Ir(ppy)(η1-R2E2)][OTf] (E = S (4), Se (5), Te (6)). Reactions of 4 and 5 with Ag(OTf) resulted in cleavage of the E-E bond and insertion of an ER group into the Ir-C(ppy) bond. The crystal structures of complexes 2-6 and [Cp∗Ir(η2-ppy-S-p-tol)(H2O)][OTf]2 have been determined. 相似文献
5.
Several (azido)iridium(III) complexes having a pentamethylcyclopentadienyl (Cp∗) group, [Cp∗Ir(N3)2(Ph2Ppy-κP)] (1: Ph2Ppy = 2-diphenylphosphinopyridine), [Cp∗Ir(N3)(Ph2Ppy-κP,κN)]CF3SO3 (2), [Cp∗Ir(N3)(dmpm)]PF6 (3: dmpm = bis(dimethylphosphino)methane), [Cp∗Ir(N3)(Ph2Pqn)]PF6·CH3OH (4·CH3OH: Ph2Pqn = 8-diphenylphosphinoquinoline), and [Cp∗Ir(N3)(pybim)] (5: Hpybim = 2-(2-pyridyl)benzimidazole) have been prepared and their crystal structures have been analyzed by X-ray diffraction. In complex 1, the Ph2Ppy ligand is only coordinated via the P atom (-κP), while in 2 it acts as a bidentate ligand through the P and N atoms (-κP,κN) to form a four-membered chelate ring. Comparing the structural parameters of the chelate ring in 2 with those of a similar five-membered chelate ring formed by Ph2Pqn in 4, it became apparent that the angular distortion in the Ph2Ppy-κP,κN ring was remarkable, although the Ir–P and Ir–N bonds in the Ph2Ppy-κP,κN ring were not elongated very much from the corresponding bonds in the Ph2Pqn-κP,κN ring. In the pybim complex 5, the five-membered chelate ring was coplanar with the pyridine and benzimidazolyl rings. With the related (azido)iridium(III) complexes analyzed previously, comparison of the structural parameters of the Ir–N3 moiety in [Cp∗IrIII(N3)(L–L′)]+/0 complexes reveals an anomalous feature of the 2,2′-bipyridyl (bpy) complex, [Cp∗Ir(N3)(bpy)]PF6. 相似文献
6.
Mayumi Sakamoto Gerald Kehr Kazuyuki Tatsumi 《Journal of organometallic chemistry》2009,694(17):2820-4038
Coordinatively unsaturated rhodium and iridium complexes having a bulky thiolate, [Cp∗M(PMe3)(SDmp)](BArF4) (1a: M = Rh; 1b: M = Ir; Dmp = 2,6-(mesityl)2C6H3, ArF = 3,5-(CF3)2C6H3), catalyzed the hydrogenation of benzaldehyde, N-benzylideneaniline, and cyclohexanone, under 1 atm of H2 at low temperatures. In these catalytic reactions, the M-H/S-H complexes [Cp∗M(PMe3)(H)(HSDmp)](BArF4) (2a: M = Rh; 2b: M = Ir) generated via H2 heterolysis by 1a or 1b were suggested to transfer both M-H hydride and S-H proton to substrates. The catalytic reactions were terminated by the dissociation of H-SDmp from the metal centers of 2a and 2b that occurs at ambient temperature under H2 atmosphere. 相似文献
7.
Speed of sound and density values for ternary systems (amino acid + salt + water): l-isoleucine/l-proline/l-glutamine in aqueous solutions of 1.5 M KCl, 1 M KNO3, and 0.5 M K2SO4 have been measured for several concentrations of amino acids at different temperatures (303.15, 308.15, 313.15, 318.15, and 323.15 K). Using speed of sound and density data, the thermodynamic parameters such as isentropic compressibility (κs), change in isentropic compressibility (Δκs) and relative change (Δκs/κ0) in isentropic compressibility have been computed. The isentropic compressibility values decrease with increase in the amino acid concentration as well as with temperature. The decrease in κs values with increase in concentration of l-isoleucine/l-proline/l-glutamine in 1.5 M KCl, 1 M KNO3, and 0.5 M K2SO4 has been ascribed to an increase in the number of incompressible zwitterions in solutions, and the formation of ‘zwitterions-ions’ and ‘zwitterions-water dipole’ entities in solutions. The decrease in κs values with increase in temperature has been attributed to the corresponding decrease of κrelax (a relaxational part of compressibility), which is dominant over the corresponding increase of κ∞ (an instantaneous part of compressibility). The trends of variation of Δκs and Δκs/κ0 with variations in solute concentration and temperature have also been discussed in terms of solute-solute and solute-solvent intermolecular/interionic interactions operative in the systems. 相似文献
8.
Xi Chu Yichuan Huang Wenhao Li Shisheng Zhao Hongyan Li Aidang Lu 《Molecules (Basel, Switzerland)》2022,27(23)
Three novel Ir(III) complexes, (ppy)2Ir(L-alanine) (Ir1) (ppy = 2-phenylpyridine), (F4ppy)2Ir(L-alanine) (Ir2) (F4ppy = 2-(4-fluorophenyl)pyridine), and (F2,4,5ppy)2Ir(L-alanine) (Ir3) (F2,4,5ppy = 2-(2,4,5-trifluorophenyl)pyridine), based on simple L-alanine as ancillary ligands were synthesized and investigated. Due to the introduction of fluorine substituents on the cyclometalated ligands, complexes Ir1–Ir3 exhibited yellow to sky-blue emissions (λem = 464–509 nm) in acetonitrile solution. The photoluminescence quantum yields (PLQYs) of Ir1–Ir3 ranged from 0.48–0.69, of which Ir3 with sky-blue luminescence had the highest PLQY of 0.69. The electrochemical study and density functional theory (DFT) calculations show that the highest occupied molecular orbital (HOMOs) energy of Ir1–Ir3 are stabilized by the introduction of fluorine substituents on the cyclometalated ligands, while L-alanine ancillary ligand has little contribution to HOMOs and lowest unoccupied molecular orbitals (LUMOs). Moreover, Ir1–Ir3 presented an excellent response to Cu2+ with a high selectivity, strong anti-interference ability, and short response time. Such a detection was based on significant phosphorescence quenching of their emissions, showing the potential application in chemosensors for Cu2+. 相似文献
9.
Ying-Feng Han 《Journal of organometallic chemistry》2008,693(3):546-550
Reactions of [M(Cp∗)Cl(μ-Cl)]2 (M = Ir(1a); M = Rh(1b)) with tridentate ligands tpt (tpt = 2,4,6-tripyridyl-1,3,5-triazine) gave the corresponding trinuclear complexes [M3(Cp∗)3(μ3-4-tpt-κN)Cl6] (M = Ir(2a); M = Rh(2b)), which can be converted into hexanuclear complexes [M6(Cp∗)6(μ3-4-tpt-κN)2(μ-Cl)6](O3SCF3)6 (M = Ir(3a); M = Rh(3b)) by treatment with AgO3SCF3, respectively. X-ray of 3b revealed that each of six pentamethylcyclopentadienyl metal moieties was connected by two μ-Cl-bridged atoms and a tridentate ligand to construct a cation triangular metallo-prism cavity with the volume of about 273 Å3 based on the distance of the two triazine moieties is 3.62 Å. 相似文献
10.
Ioana Vidican 《Journal of solid state chemistry》2003,170(2):203-210
Single crystals of K3RESi2O7 (RE=Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) were grown from a potassium fluoride flux. Two different structure types were found for this series. Silicates containing the larger rare earths, RE=Gd, Tb, Dy, Ho, Er, Tm, Yb crystallize in a structure K3RESi2O7 that contains the rare-earth cation in both a slightly distorted octahedral and an ideal trigonal prismatic coordination environment, while in K3LuSi2O7, containing the smallest of the rare earths, lutetium is found solely in an octahedral coordination environment. The structure of K3LuSi2O7 crystallizes in space group P63/mmc with a=5.71160(10) Å and c=13.8883(6) Å. The structures containing the remaining rare earths crystallize in the space group P63/mcm with the lattice parameters of a=9.9359(2) Å, c=14.4295(4) Å, (K3GdSi2O7); a=9.88730(10) Å, c=14.3856(3) Å, (K3TbSi2O7); a=9.8673(2) Å, c=14.3572(4) Å, (K3DySi2O7); a=9.8408(3) Å, c=14.3206(6) Å, (K3HoSi2O7); a=9.82120(10) Å, c=14.2986(2) Å, (K3ErSi2O7); a=9.80200(10) Å, c=14.2863(4) Å, (K3TmSi2O7); a=9.78190(10) Å, c=14.2401(3) Å, (K3YbSi2O7). The optical properties of the silicates were investigated and K3TbSi2O7 was found to fluoresce in the visible. 相似文献
11.
Hydrothermal synthesis in the K-Mo oxide system was investigated as a function of the pH of the reaction medium. Four compounds were formed, including two K2Mo4O13 phases. One is a new low-temperature polymorph, which crystallizes in the orthorhombic, space group Pbca, with Z=8 and unit cell dimensions a=7.544(1) Å, b=15.394(2) Å, c=18.568(3) Å. The other is the known triclinic K2Mo4O13, whose structure was re-determined from single crystal data; its cell parameters were determined as a=7.976(2) Å, b=8.345(2) Å, c=10.017(2) Å, α=107.104(3)°, β=102.885(3)°, γ=109.760(3)°, which are the standard settings of the crystal lattice. The orthorhombic phase converts endothermically into triclinic phase at ca. 730 K with a heat of transition of 8.31 kJ/mol. 相似文献
12.
Jiawei Hu Hung-Hsin Shih Peipei Sun Chien-Hong Cheng 《Journal of organometallic chemistry》2008,693(16):2798-2802
A rigid ligand benzo[de]benzo[4,5]imidazo[2,1-α]isoquinolin-7-one (biio) was designed and conveniently synthesized, and the corresponding bis-cyclometalated iridium complex (biio)2Ir(acac) (acac = acetylacetone) was prepared. The light emitting and electrochemical properties of this complex were studied. The complex has the characters of simply synthetic procedure and strong phosphorescence. The electroluminescent device using this complex as dopant was fabricated. The device had the structure of ITO/NPB (40 nm)/Ir complex:CBP (7%, 30 nm)/BCP (15 nm)/Alq3 (30 nm)/LiF (1 nm)/Al (100 nm). The maximum emission of the device was at 496 nm. The maximum brightness of the device can reach 79640 cd m−2 with an external quantum efficiency of 12.1% and a maximum current efficiency of 31.7 cd A−1. 相似文献
13.
Titanium trifluoride TiF3 has the distorted ReO3 structure composed of corner sharing TiF6 octahedra linked with Ti-F-Ti bridges. Potassium fluoride KF was inserted into the bridges using high-pressure and high-temperature conditions (5 GPa, 1000-1200 °C). When the molar ratio KF/TiF3≥1, a few low dimensional compounds were obtained forming non-bridged F ions. At the composition KF/TiF3=1/2, a new compound KTi2F7 was formed, which crystallizes with the space group Cmmm and the lattice parameters of a=6.371(3), b=10.448(6), c=3.958(2) Å, consisting of edge-sharing pentagonal bipyramids [TiF7] forming ribbons running along the a axis. The ribbons are linked by corners to construct a three-dimensional framework without forming non-bridged F ions. The compound is antiferromagnetic with the Néel temperature TN=75 K, and the optical band gap was 6.4 eV. A new fluoride K2TiF5 (KF/TiF3=2) with the space group Pbcn and the lattice parameters of a=7.4626(2), b=12.9544(4) and c=20.6906(7) Å was also obtained by the high pressure and high temperature treatment (5 GPa at 1000 °C) of a molar mixture of 2 KF+TiF3. The compound contains one-dimensional chains of corner-sharing TiF6 octahedra. 相似文献
14.
Thermolysis of Ni(OTf)2 in 2-phenyl-pyridine or 2-tolyl-pyridine afforded the cationic chelate derivatives, [bis(2-aryl-pyridine)Ni{(2-aryl-κC2)pyridine-κN}]OTf (aryl = phenyl, 1a; tolyl, 1b). Addition of KBr to 1a and LiBr to 1b provided the bromides, (2-aryl-pyridine)BrNi{(2-aryl-κC2)pyridine-κN} (aryl = phenyl, 2a; tolyl, 2b). When subjected to KOtBu in Et2O, the bromides generated the entitled bis-cyclometalated compounds, Ni{(2-aryl-κC2)pyridine-κN}2 (aryl = phenyl, 3a; tolyl, 3b). These compounds insert diphenylacetylene into one cyclometalate arm to produce [(2-aryl-κC2)pyridine-κN]Ni[2-(2-(1,2-diphenylethenyl-κC2)aryl)pyridine-κN] (aryl = phenyl, 4a; p-tolyl, 4b). X-ray crystallographic studies were conducted on 1a, 2a, 3a and 4a, and a brief DFT study of 3a confirmed its low spin configuration and rippled geometry. 相似文献
15.
Cyclometalated iridium(III) complexes have been synthesized for use in a variety of photophysical applications, including polymer light emitting diodes (PLEDs). A series of new complexes with one electrochemically polymerizable ligand and two phenylpyridine(ppy)-based ligands have been prepared: [Ir(ppy)2L][PF6](1), [Ir(F-mppy)2L][PF6](2), and [Ir(Br-mppy)2L][PF6](3), where L = 3,8-bis(2,2′-bithien-5-yl)-1,10-phenanthroline. The ancillary ppy ligands can be easily varied synthetically to tune emission color of the monomer from blue–green to red. The solid state structure of complex 1 has been obtained by single crystal X-ray crystallography. Conducting polymer materials have been prepared by electropolymerization of monomers and were characterized through XPS analysis and spectroscopic studies. 相似文献
16.
Waldemar Stampor Jakub Mężyk Jan Kalinowski Massimo Cocchi Dalia Virgili Valeria Fattori Piergiulio Di Marco 《Macromolecular Symposia》2004,212(1):509-514
We demonstrate high-efficient simple electrophosphorescent devices comprised of tris{4-[N-(3-methylphenyl)anilino]phenyl}amine (m-MTDATA) dispersed in a polycarbonate (PC) matrix as a hole-transporting layer (HTL), and 2-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD) as an electron-transporting layer (ETL). The HTL doped with a complex phosphor fac-tris(2-phenylpyridine)iridium, [Ir(ppy)3], and/or 5,6,11,12-tetraphenyltetracene (rubrene) fluorescent dye is shown to act as an emitter. Devices containing [Ir(ppy)3] as a single HTL dopant show the highest external quantum efficiency (QE) reaching 9 % (photon/electron) due to direct electron-hole recombination on phosphorescent [Ir(ppy)3]. A decrease in QE of one order of magnitude at high current densities is observed in all devices. Addition of rubrene to [Ir(ppy)3]-doped devices shifts the maximum QE towards larger current densities. 相似文献
17.
We have prepared a new layered oxycarbide, [Al5.25(5)Si0.75(5)][O1.60(7)C3.40(7)], by isothermal heating of (Al4.4Si0.6)(O1.0C3.0) at 2273 K near the carbon-carbon monoxide buffer. The crystal structure was characterized using X-ray powder diffraction, transmission electron microscopy and energy dispersive X-ray spectroscopy (EDX). The title compound is trigonal with space group R3?m (centrosymmetric), Z=3, and hexagonal cell dimensions a=0.32464(2) nm, c=4.00527(14) nm and V=0.36556(3) nm3. The atom ratios Al:Si were determined by EDX, and the initial structural model was derived by the direct methods. The final structural model showed the positional disordering of one of the three types of Al/Si sites. The reliability indices were Rwp=4.45% (S=1.30), Rp=3.48%, RB=2.27% and RF=1.25%. The crystal is composed of three types of domains with nearly the same fraction, one of which has the crystal structure of space group R3¯m. The crystal structure of the remaining two domains, which are related by pseudo-symmetry inversion, is noncentrosymmetric with space group R3m. 相似文献
18.
Three novel metal polyphosphides, α-SrP3, BaP8, and LaP5, were prepared in BN crucibles by the reaction of the respective stoichiometric mixtures under a high pressure of 3 GPa at 950-1000°C. Their crystal structures were determined from single-crystal X-ray data (α-SrP3: space group C2/m, a=9.199(6) Å, b=7.288(3) Å, c=5.690(3) Å, β=113.45(4)°, Z=4, R1/wR2=0.0684/0.1180 for 471 observed reflections and 22 variables; BaP8: space group P−1, a=6.762(2) Å, b=7.233(2) Å, c=8.567(2) Å, α=86.32(2)°, β=84.31(2)°, γ=70.40(2)°, Z=2, R1/wR2=0.0476/0.1255 for 2702 observed reflections and 82 variables; LaP5: space group P21/m, a=4.885(1) Å, b=9.673(3) Å, c=5.577(2) Å, β=105.32(2)°, Z=2, R1/wR2=0.0391/0.1034 for 1272 observed reflections and 31 variables). α-SrP3 is isostructural with SrAs3 and the crystal structure consists of two-dimensional puckered polyanionic layers ∞2[P3]2− that stack along the c-axis yielding channels occupied by Sr2+ counterions. BaP8 crystallizes in a new structure type which contains a three-dimensional infinite polyanionic framework ∞3[P3]2−, with large channels hosting the barium cations. LaP5 is a layered compound containing ∞2[P5]3− polyanionic layers separated by La3+ ions. All three compounds exhibit expected diamagnetic behaviors. 相似文献
19.
A new ternary compound, U3Co2Ge7, has been synthesized from the corresponding elements by a high temperature reaction using molten tin flux. It crystallizes in the orthorhombic La3Co2Sn7-type (Pearson's symbol oC24, space group Cmmm, No. 65) with lattice parameters determined from single-crystal X-ray diffraction as follows: a=4.145(2) Å; b=24.920(7); c=4.136(2) Å, V=427.2(3) Å3. Structure refinements confirm an ordered structure having two crystallographically inequivalent uranium atoms, occupying sites with dissimilar coordination. U3Co2Ge7 orders ferromagnetically below 40 K and undergoes a consecutive magnetic transition at 20 K. These results have been obtained from temperature- and field-dependent magnetization, resistivity and heat-capacity measurements. The estimated Sommerfeld coefficient γ=87 mJ/mol-U K2 suggests U3Co2Ge7 to be a moderately heavy-fermion material. 相似文献
20.
Sr2Co2O5 with the perovskite-related brownmillerite structure has been synthesised via quenching, with the orthorhombic unit cell parameters a=5.4639(3) Å, b=15.6486(8) Å and c=5.5667(3) Å based on refinement of neutron powder diffraction data collected at 4 K. Electron microscopy revealed L-R-L-R-intralayer ordering of chain orientations, which require a doubling of the unit cell along the c-parameter, consistent with the assignment of the space group Pcmb. However, on the length scale pertinent to NPD, no long-range order is observed and the disordered space group Imma appears more appropriate. The magnetic structure corresponds to G-type order with a moment of 3.00(4) μB directed along [1 0 0]. 相似文献