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Abstract: Electron doped double perovskite compound (Sr2− x Sm x )FeMoO6 (0≤x≤0.25) has been synthesized by solid-state reaction at high temperature. Crystal structure and magnetic properties of the compounds have been investigated by X-ray powder diffraction (XRD) and magnetic measurements. XRD revealed that all the compounds were of single phase and belonged to a I4/m lattice. The degree of cationic ordering on the B site was decreased pronouncedly by the electron doping. Different from the results of La- and Nd-doped Sr2FeMoO6, Curie temperature (T C) of (Sr2− x Sm x )FeMoO6 decreased first with the doping and then increased beyond x=0.15, indicating that steric effect was enhanced as the radius of rare-earth ions decreased. Saturation magnetization (M S) of the compounds decreased with the doping level and anti-site (AS) concentration. Sm moment showed a considerable contribution to M S at low temperature, leading to an abrupt drop of M S between x=0.1 and 0.15. [Copyright &y& Elsevier]

The electronic transport properties of the ordered double perovskite oxides Sr2FexMo2−xO6 (0.8&les;x&les;1.5) have been investigated. In this system, the samples (x&ges;1.2) are semiconducting in the temperature range of 4.2&les;T&les;300 K. A metal–semiconductor transition occurs when x<1.2 and the transition temperature TMS decreases obviously as the Fe content decreases. Rietveld refinement of the X-ray powder diffraction profiles indicates that the crystal structure of the compounds Sr2FexMo2−xO6 changes from a tetragonal I4/mmm lattice to a cubic Fm3¯m lattice around x=1.2. [Copyright &y& Elsevier]

The structural transition and atomic ordering of a new series of ordered double perovskite oxides Sr2FexMo2−xO6 (0.8≤x≤1.5) have been studied by X-ray powder diffraction (XRD). Rietveld refinement of the powder diffraction profiles indicates that the crystal structure of the compounds Sr2FexMo2−xO6 changes from a tetragonal I4/mmm lattice to a cubic Fm3¯m lattice around x=1.2 and the lattice parameters decrease slightly as Fe content increases. The degree of ordering in Sr2FexMo2−xO6 exhibits a maximal at x=0.95 and decreases as x deviates from 0.95. [Copyright &y& Elsevier]

A novel surface modified complex strontium titanate used as dispersion particles in an electrorhelogical fluid with an extraordinary high yield stress was synthesized by means of a modified sol–gel technique and characterized by X-ray powder diffraction. The structure model free full profile fitting technique was used to derive the crystallographic data of the compound, which crystallized in a monoclinic lattice with a=13.6822(7), b=14.5549(6), c=12.7423(5) A˚ and β=91.803(2)°. Deliberate examination of the XRD pattern indicates that the most probable space group of the compound is P21/n. A possible composition of the complex strontium titanate is Sr[TiO4(C2O4)2].3H2O with eight chemical formula units per unit cell, leading to a calculated density of DX=2.25 g/cm3 in good agreement with the measured density of Dm=2.28(5) g/cm3. [Copyright &y& Elsevier]

The crystal structure and magnetic properties of Sr2(Fe1−xCrx)MoO6 (0&les;x&les;0.4) have been investigated. In contrast to Sr2(Fe1−xMnx)MoO6 and Sr2Fe(Mo1−xWx)O6, the Cr doping results in a decrease of cationic ordering in Sr2(Fe1−xCrx)MoO6. The saturation magnetization decreases with x and exhibits a linear dependence on the anti-site defect concentration. All the samples exhibit a semiconductor–metal transition. The low-field magnetoresistance increases with the saturation magnetization in a non-linear way. By assuming a preferential occupation of the Cr ions at the Mo sites, the dependence of magnetization on the Cr content can be well explained within a simple ferrimagnetic model. [Copyright &y& Elsevier]

Crystal structures of compounds at ambient temperature in the pseudobinary system Gd5Ge4–La5Ge4 were studied by X-ray powder diffraction (XRD). There exist three single-phase regions in this system. The crystal structure of Gd5Ge4, La5Ge4 and Gd3La2Ge4, which are prototype compounds in three phase regions, respectively, were reported. The Gd5Ge4 and La5Ge4 crystallize in the orthorhombic Sm5Ge4-type structure with space group Pnma. The ternary intermediate compound Gd3La2Ge4, which is determined for the first time, crystallizes in the monoclinic Gd5Si2Ge2-type structure with space group P1121/a. The Rietveld powder diffraction profile fitting technique was used for the refinement of crystal structure. The lattice parameters, atomic occupations, interatomic distances of the Gd5Ge4, La5Ge4 and Gd3La2Ge4 compounds were derived. [Copyright &y& Elsevier]

The magnetic properties of Pr5Si4−xGex (x=0.0, 1.0, 2.0, 2.5, 3.0, 3.5, 4.0) were investigated by magnetic measurements. The compounds Pr5Si4−xGex crystallize in the tetragonal Zr5Si4-type structure for x=0.0 and 1.0, in the monoclinic Gd5Si2Ge2-type structure for x=2.0 and 2.5; and in the orthorhombic Sm5Ge4-type structure for x=3.0–4.0. Unlike the heavy rare earth RE5Si4−xGex (RE=Gd, Tb, Dy) system, the Curie temperature of this system exhibits the following features: the Curie temperature of the compound increases with the increasing of the Ge content in the tetragonal phase region, whereas it shows a weak dependence on the Ge content in the monoclinic phase region and decreases in the orthorhombic phase region. All of the compounds in this system may have a canted magnetic structure. [Copyright &y& Elsevier]

High-temperature (1273 K) phase relationships in the pseudobinary system RE5Si4–RE5Ge4 (RE=Nd and Pr) were studied by X-ray powder diffraction (XRD). Three structurally distinct phase regions exist in the Nd5Si4−xGex system: the Nd5Si4-based solid solution crystallizing in the tetragonal Zr5Si4-type structure with space group P41212, the Nd5Ge4-based solid solution crystallizing in the orthorhombic Gd5Ge4-type structure with space group Pnma and a ternary intermediate phase crystallizing in the monoclinic Gd5Si2Ge2-type structure with space group P1121/a. In the Pr5Si4−xGex system, there are only two structurally distinct phase regions: the Pr5Si4-based solid solution crystallizing in the tetragonal Zr5Si4-type structure with space group P41212 and the Pr5Ge4-based solid solution crystallizing in the orthorhombic Gd5Ge4-type structure with space group Pnma. The Rietveld powder diffraction profile fitting technique was used for the refinement of crystal structures. The lattice parameters, atomic positions and interatomic distances in the high-temperature Nd5Si2.8Ge1.2, Nd5Si2Ge2 and Pr5Si2Ge2 compounds were derived. [Copyright &y& Elsevier]

The crystal structure and magnetic properties of ternary compounds Nd5Si4−xGex (x=1.2 and 2) were investigated by means of X-ray powder diffraction and magnetic measurements. The as-cast samples α-Nd5Si2.8Ge1.2 and α-Nd5Si2Ge2 crystallize in the orthorhombic Gd5Si4-type structure with space group Pnma and the monoclinic Gd5Si2Ge2-type structure with space group P1121/a, respectively. The samples β-Nd5Si2.8Ge1.2 and β-Nd5Si2Ge2 annealed at 1273 K all crystallize in the tetragonal Zr5Si4-type structure with space group P41212. All phases of α-Nd5Si2.8Ge1.2, β-Nd5Si2.8Ge1.2, α-Nd5Si2Ge2 and β-Nd5Si2Ge2 exhibit a spin glasslike behavior and may have a canted magnetic structure. The Curie temperature shows a strong dependence on the crystal structure of the compounds. The average interatomic distances of magnetic Nd atoms and the amount of the covalent (Si,Ge)–(Si,Ge) bond pairs in these phases are different, which may be responsible for their different magnetic properties. [Copyright &y& Elsevier]

Phase relationships at ambient temperature in the pseudobinary system Nd5Si4–Nd5Ge4 were studied by X-ray powder diffraction (XRD). Four structurally distinct phase regions exist in this system. The Nd5Si4-based solid solution in which Ge statistically substitutes for Si crystallizes in the tetragonal Zr5Si4-type structure with space group P41212. The Nd5Ge4-based solid solution in which Si statistically substitutes for Ge crystallizes in the orthorhombic Gd5Ge4-type structure with space group Pnma. There are two ternary intermediate phases, which crystallize in the orthorhombic Gd5Si4-type structure with space group Pnma and the monoclinic Gd5Si2Ge2-type structure with space group P1121/a. The Rietveld powder diffraction profile fitting technique was used for refinement of the crystal structure. The lattice parameters, atomic positions and interatomic distances for Nd5Si4, Nd5Si2.8Ge1.2, Nd5Si2Ge2 and Nd5Ge4 were derived. [Copyright &y& Elsevier]

The structure and the magnetic properties of the Gd5Sn4 compound have been investigated by means of X-ray diffraction (XRD) and magnetization measurements. Temperature dependent XRD investigation reveals that there is no structural transition around the temperature at which the first-order magnetic transition occurs in this compound, i.e. the compound retains the Sm5Ge4-type structure from 80 K(TC), which is different from the Gd5(Si, Ge)4 system. Based on the Rietveld refinement of the XRD pattern of Gd5Sn4 compound, we show that the unit cell volume exhibits a dip near the Curie temperature, i.e. a negative coefficient of thermal expansion α&ap;−1.5×10−4 K−1 from 82 to 90 K and a positive coefficient α&ap;2.2×10−4 K−1 from 90 to 98 K. The coefficient of thermal expansion from 98 to 298 K is only 2.5×10−5 K−1. [Copyright &y& Elsevier]

Abstract: Crystal structure and magnetic properties of the Nd1−x Gd x Co9.5V2.5 compounds (x=0–1) have been investigated. The compounds crystallize in the tetragonal ThMn12 structure with space group I4/mmm. The lattice parameters a, c and the unit cell volume V decrease with the increase of Gd content. The Curie temperature of Nd1−x Gd x Co9.5V2.5 increases monotonically upon the substitution of Gd for Nd. The critical field required to induce the magnetization jump decreases with increasing Gd content. The metamagnetic transition phenomenon becomes less obvious and even disappears with the substitution of Gd for Nd. The required for the metamagnetic transition increased with increasing Gd content at low substitution content. The saturation moment M S of the compounds decreases first then increases with the increased Gd content. [Copyright &y& Elsevier]

Abstract: The crystal and magnetic structures of the composite compound Nd2Co6Fe have been investigated by high-resolution neutron powder diffraction and X-ray powder diffraction. The compound crystallizes in the hexagonal Ce2Ni7-type structure consisting of Nd(Co,Fe)2 and Nd(Co,Fe)5 structural blocks alternately stacked along the c-axis. Multi-pattern Rietveld refinement of neutron diffraction and X-ray diffraction data at room temperature reveal that substitution of Fe for Co occurs exclusively in the Nd(Co,Fe)5 structural blocks. The preferential occupation of the Fe atoms in the structure is discussed based on the mixing enthalpy between Nd and Fe atoms and on the lattice distortions. In agreement with the reported magnetic phase diagram of the Nd2Co7−x Fe x compounds, magnetic structure models with the moments of all atoms in the ab plane at 300K and along the c-axis at 450K provide a satisfactory fitting to the experimental neutron diffraction data. The refinement results show that the atomic moments of (Co,Fe) atoms within the Nd(Co,Fe)5 blocks decrease slightly with temperature, whereas the atomic moments of Nd in the compound and of (Co,Fe) atoms at the interface between the Nd(Co,Fe)2 and Nd(Co,Fe)5 blocks are reduced significantly. [Copyright &y& Elsevier]

Abstract: Double perovskite compounds (Sr2−x Eu x )FeMoO6 (0≤x≤0.3) were prepared by solid-state reaction at high temperature. Crystal structure, magnetic and transport properties of the compounds were investigated. The crystal structure of the compounds changes from an I4/m lattice to an Fm3¯m lattice around x=0.1. The unit-cell volume decreases with the doping level in both the I4/m lattice and the Fm3¯m lattice. The resistivity of the compounds shows a metal–semiconductor transition, and the transition temperature T M–S increases with the doping level. However, Curie temperature (T C) of the compounds exhibits a weak dependence on the doping level. The saturation magnetization (M S) at 100K varies almost linearly with the anti-site defect concentration and agrees well with the simple FIM model. In contrast to the Ce-, Pr-, Nd- and Sm-doped Sr2FeMoO6, the difference of M S of (Sr2−x Eu x )FeMoO6 between 5 and 100K indicates that the moment of Eu3+ is antiparellel to that of Fe3+ at low temperature. [ABSTRACT FROM AUTHOR]

Abstract: The structural and magnetic properties of the Nd2Co7−x Fe x compounds related to R m+n T2m+5n series (R=rare earth, T=transition metal) were investigated by means of X-ray diffraction and magnetic measurements. The compounds crystallize in the Ce2Ni7-type structure with the space group P63/mmc between x =0.0 and 2.1. For higher Fe content the Nd2(CoFe)7 either coexists with the Nd(CoFe)3 phase (x >2.1) or decomposes to Nd(CoFe)3 +Nd2(CoFe)17 (x >2.4). The single phase Nd2Co7−x Fe x compounds exhibit two spin-reorientation transitions (SRT) for x <1.5. The substitution of Fe for Co elevates both the spin-reorientation transition temperatures for x <1.5 and finally leads to a single ferromagnetism to paramagnetism transition for x ≥1.5. A magnetic phase diagram is constructed based on the magnetic measurements, thermogravimetry analysis under a low magnetic field and X-ray diffraction of magnetically aligned samples. The saturation magnetization of the compounds increases gradually first with the Fe content for x ≤0.20, substantially for 0.20< x <1.5, and then decreases for x >1.5, which can be elucidated by a depletion effect of d band electrons due to the substitution of Fe for Co and the spin-flipping due to an enhanced d band splitting. [Copyright &y& Elsevier]

Abstract: The crystal structure and physical properties of Bi1− x Gd x FeO3 ceramics with x ≤0.5 have been studied by X-ray diffraction, differential scanning calorimetry, dielectric and magnetic measurements. Bi1− x Gd x FeO3 compounds crystallize at room temperature in R3c structure for x <0.08 and in Pbnm structure for x ≥0.3. The R3c phase transforms to the Pbnm phase as temperature increases. Temperature-dependent dielectric response and low-temperature X-ray diffraction indicate a phase transition of the Pbnm phase at low-temperature. Detailed structural analysis indicates that the interaction between Bi and O plays an important role in the evolution of structure and physical properties. A phase diagram is constructed to illustrate the physical property–composition–temperature relations. [Copyright &y& Elsevier]

Abstract: We present a systematic investigation on the structural and magnetic properties of Zn1− x Co x O nanoparticles synthesized by an auto-combustion method. The single-phase Zn1− x Co x O crystallize in the wurtzite-type structure with a homogeneity range as large as x≈0.30, which enables the observation of some anomalies. The lattice parameter a and the unit cell volume V increase with the Co content, and anomalies are discernable around x=0.15 on the a−x and V−x curves. The magnetization data show no evidence of ferromagnetic (FM) ordering in our samples down to T=5K, and the magnetization at 5K and 5T exhibits a maximum around x=0.125. Based on the detailed analysis of the magnetization data and the donor impurity band exchange model, the anomalies on composition dependence of both the lattice parameters and magnetization can be associated with an occurrence of cation percolation around the threshold x p (≈1.5/Z=0.125 for three-dimensional lattice with coordination number Z=12). Within the framework of the donor impurity band exchange model, the absence of FM in the well-characterized Zn1− x Co x O can be attributed to insufficient donor electron concentration. [Copyright &y& Elsevier]

Abstract: The crystal structure and magnetic properties of mixed rare earth Nd2−x Er x Fe17 compounds (0≤ x ≤2.0) were investigated by means of X-ray powder diffraction (XRD) and magnetic measurements. The compounds crystallize in the rhombohedral Th2Zn17-type structure for x ≤0.5 and in the hexagonal Th2Ni17-type structure for x =2.0. Coexistence of the Th2Zn17- and the Th2Ni17-type structures is observed for x =1.0 and 1.5. Violating the Gibbs’ phase rule for a binary system, the linear decrease of the unit-cell volume with the Er concentration persists even in the two-phase region, implying an allotropic character of the coexisting Th2Zn17 and Th2Ni17 phases in the samples with x =1.0 and 1.5. Thermomagnetic measurements show only one magnetic ordering temperature for the samples in the two-phase region, but temperature dependent XRD reveal obvious magnetovolume effects in both the phases around the magnetic ordering temperature. The saturation magnetization of the compounds exhibits a linear dependence on the Er concentration, indicating an ideal mixing effect of the rare earths on the magnetization in spite of the different crystal structures of the parent compounds. [Copyright &y& Elsevier]

Abstract: The structural and magnetic properties of Nd1− x Tb x Fe10.5Mo1.5 (, 0.2, 0.4, 0.6, 0.8, 1.0) compounds have been investigated by means of X-ray diffraction and magnetic measurements. All the investigated compounds crystallize in the tetragonal ThMn12-type structure with I4/mmm space group. The lattice parameters a, c and the unit-cell volume V decrease with increasing x. The Curie temperatures T C are almost independent x. There exists a unique spin-reorientation transition for the end compositions of Nd1− x Tb x Fe10.5Mo1.5 compounds with and , while two spin-reorientation transitions are observed for . The room-temperature magnetocrystalline anisotropy of Nd1− x Tb x Fe10.5Mo1.5 compounds changes from uniaxial to planar with increasing x content. Based on magnetic measurements, a magnetic phase diagram of Nd1− x Tb x Fe10.5Mo1.5 compounds is constructed. By minimizing the magnetocrystalline anisotropy energy, a theoretical magnetic phase diagram for the Nd1− x Tb x Fe10.5Mo1.5 system is derived, showing a reasonable agreement with the observations. [Copyright &y& Elsevier]

Abstract: The crystal structure and magnetic properties of Nd2−x Tb x Fe17 and NdTbFe17−y Al y compounds were studied by means of X-ray diffraction and magnetization measurements. All the samples show the rhombohedral Th2Zn17-type structure with space group . For Nd2−x Tb x Fe17 compounds, the lattice parameters decrease with increasing Tb concentration, and the Curie temperature increases with the Tb content while the saturation magnetization decreases linearly at a rate of 10.54μ B/f.u. per Tb atom. For NdTbFe17−y Al y compounds, the substitution of Al for Fe leads to an increase in lattice parameters a, c and unit-cell volume V. The Al atoms preferentially occupy 18h site at low Al concentration whereas prefer to occupy 6c and 18f sites at high Al concentration. The Curie temperature increases with Al content up to y =3 then decreases for 3≤ y ≤8. X-ray diffraction of magnetically pre-aligned samples indicates that the easy magnetization direction of the samples changes from planar to c-axial with increasing aluminum concentration. The saturation magnetization of compounds decreases with increasing Al concentration. [Copyright &y& Elsevier]

Abstract: The crystal structure and magnetic properties of a series of ordered double perovskite oxides (Sr2−3 x La2 x Ba x )FeMoO6 () have been investigated. X-ray powder diffraction reveals that the crystal structure of the compounds changes from a tetragonal I4/m lattice to a cubic lattice around . Though the nominal average size of the A site cation of (Sr2−3 x La2 x Ba x )FeMoO6 is designed to be almost independent of x, the refinements of the crystal structure show that the lattice constants increase with x in both the tetragonal and the cubic phase regions due to electron doping. As the x increases, the degree of cationic ordering on the B site is decreased pronouncedly, while the Curie temperature of the compounds is nearly unchanged. The saturation magnetization of the compounds decreases with x and shows a linear dependence on the degree of cation ordering. The resistivity of the parent compound shows a semiconducting behavior below room temperature, but those of the doped samples exhibit a metal–semiconductor transition. A correlation between the resistivity and metal-semiconducting transition temperature (T M−S) is observed. The resistivity and T M−S of the compounds decrease with x for and increase for . Magnetoresistance of the compounds is reduced by the La/Ba doping. All these observations can be understood based on the interplay of the electron doping, change in bandwidth and the anti-site defect concentration. [Copyright &y& Elsevier]

Abstract: TbFe12− x Mo x compounds (x=0.5–3.0) with the tetragonal ThMn12-type structure have been synthesized. The structural and the magnetic properties of the compounds have been investigated by means of X-ray diffraction and magnetic measurements. The lattice parameters a, c and the unit-cell volume V increase with increasing Mo content. Both the Curie temperature T C and the saturation magnetization M S at 5K decrease monotonically with increasing Mo content. The molecular field coefficients n FeFe and n RFe have been estimated from a mean-field analysis of the Curie temperature of the compounds. The easy magnetization direction at room temperature changes with increasing Mo content from planar to probably cone and finally to uniaxial. The decrease of saturation magnetization with increasing Mo content may be caused by the reduction of the due to hybridization of the Fe and Mo d-bands. [Copyright &y& Elsevier]

Abstract: The crystal structure and magnetic properties of (Nd x R1− x )3Fe24Cr5 (R=Gd and Tb) compounds with have been investigated by means of X-ray diffraction and magnetic measurements. All the samples are single phase and crystallize in the Nd3(Fe,Ti)29-type structure with space group A2/m. As the Nd content increases, the lattice parameters a, b, c and the unit-cell volume V increase in both the (Nd x Gd1− x )3Fe24Cr5 and the (Nd x Tb1− x )3Fe24Cr5 compounds due to the lanthanide contraction. The room-temperature easy magnetization direction changes to the [040] direction with increasing Nd content. The Curie temperature of (Nd x Gd1− x )3Fe24Cr5 decreases monotonically upon substitution of Nd for Gd, while the Curie temperature of the (Nd x Tb1− x )3Fe24Cr5 compounds decreases with the Nd content for and increases for . The saturation magnetization M S increases monotonically with increasing Nd content for both compound systems and can be described in terms of a simple dilution model. [Copyright &y& Elsevier]

The structure and magnetic properties of the SmCo9.8V2.2 compound were investigated by means of X-ray diffraction analysis and magnetic measurement. SmCo9.8V2.2 crystallizes in a tetragonal structure with space group I4/mmm. The lattice parameters are a=8.3802(1) A˚ and c=4.7047(1) A˚. Both the atomic size effect and enthalpy effect favor a preferential occupation of V on the 8i site. Magnetic measurements indicate that the SmCo9.8V2.2 compound is ferromagnetic with a Curie temperature of 360 K. The easy magnetization direction of SmCo9.8V2.2 is perpendicular to the c-axis. The saturation magnetization and the magnetocrystalline anisotropy field of the SmCo9.8V2.2 compound at 5 K are 35.4 emu/g and 77 kOe, respectively. [Copyright &y& Elsevier]

The crystal structure and magnetic properties of TbFe10−xNixSi2 compounds have been investigated by means of X-ray diffraction and magnetic measurements. It is revealed that Ni substitution for Fe results in a slight variation of the Curie temperature, but a salient decrease of the spin-reorientation temperature of the compounds. A spin-phase diagram of TbFe10−xNixSi2 is constructed. At room temperature the compounds show planar magnetocrystalline anisotropy for x&les;1.5, but easy-axis anisotropy for x>1.5. Temperature dependent X-ray diffraction indicates a noticeable magnetostriction around the spin-reorientation temperature. [Copyright &y& Elsevier]

Phase relationships at ambient temperature in the pseudobinary system Pr5Si4–Pr5Ge4 were studied by X-ray powder diffraction (XRD). Three structurally distinct phase regions exist in this system. The Pr5Si4-based solid solution where Ge statistically substitutes for Si crystallizes in the Zr5Si4-type tetragonal structure with space group P41212. The Pr5Ge4-based solid solution where Si statistically substitutes for Ge crystallizes in Sm5Ge4-type orthorhombic structure with space group Pnma. The crystal structure of a ternary intermediate phase, which exists between 1.65≤x≤2.6, is determined for the first time, and shown to be the Gd5Si2Ge2-type monoclinic structure with space group P1121/a. The Rietveld powder diffraction profile fitting technique was used for the refinement of crystal structure. The lattice parameters, atomic occupations, interatomic distances of the Pr5Si4, Pr5Ge4 and Pr5Si2Ge2 compounds were derived. [Copyright &y& Elsevier]

The structural and magnetic properties of the ternary GdFe11Re compound were investigated by means of X-ray diffraction analysis and magnetic measurement. GdFe11Re crystallizes in a tetragonal structure with space group I4/mmm. The lattice parameters are a=8.5339 A˚ and c=4.7603 A˚. The results of Rietveld refinement of powder XRD data revealed that the Re atoms preferentially occupy the 8i site. This is basically due to the atomic size effect dominating over the enthalpy effect. Magnetic measurements indicated that the GdFe11Re compound is ferromagnetic with a Curie temperature of 518 K. It was found that the easy magnetization direction of GdFe11Re is along the c-axis. The saturation moment and the magnetocrystalline anisotropy field of the GdFe11Re compound at 5 K are 16.28 μB/f.u. and 56.4 kOe, respectively. [Copyright &y& Elsevier]

The crystal structures of La5Si4 and Nd5Si4 were studied by X-ray powder diffraction (XRD). Both of these compounds crystallize in the tetragonal Zr5Si4 type structure with space group P41212. The Rietveld powder diffraction profile fitting technique was used for the refinement of the crystal structure. The lattice parameters are a=8.0467(0) A˚, c=15.4476(1) A˚ for La5Si4 and a=7.8694(0) A˚, c=14.8077(1) A˚ for Nd5Si4. Atomic occupations, interatomic distances and coordination polyhedra in La5Si4 and Nd5Si4 were derived. [Copyright &y& Elsevier]