Showing papers on "Lattice constant published in 1991"
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TL;DR: Applications of a density-functional theory of nonuniform fluid mixtures to the fluid-solid transition of simple binary mixtures of hard spheres demonstrates the importance of relative atomic sizes in determining lattice constants and suggests that for sufficiently small disparities in atomic size Vegard's law may also hold along the fluid -solid coexistence curve.
Abstract: Vegard's law is an approximate empirical rule which holds that a linear relation exists, at constant temperature, between the crystal lattice constant of an alloy and the concentrations of the constituent elements. Applications of a density-functional theory of nonuniform fluid mixtures to the fluid-solid transition of simple binary mixtures of hard spheres demonstrates the importance of relative atomic sizes in determining lattice constants and suggests that for sufficiently small disparities in atomic size Vegard's law may also hold along the fluid-solid coexistence curve.
2,000 citations
TL;DR: In this article, the tendency towards a specific preferred orientation is discussed on the basis of strain and surface energies, and a decrease in lattice parameter with increasing temperature was observed on annealing.
646 citations
TL;DR: In this article, a series of single-phase, isostructural f.c. superconductors with composition A3C60 (where A is K, Rb, Cs or a mixture of these) were presented.
Abstract: THE discovery of conductivity1 in AxC60 (where A represents an alkali metal) and superconductivity2 in KxC60 has been followed by reports of superconductivity in other alkali-metal-doped full-erides with transition temperatures as high as 33 K (ref. 3). Elucidation of phase diagrams and understanding the relationship between structure and superconducting properties is essential to a detailed understanding of superconductivity in these systems. So far, structural data have been reported only for the non-conducting, intercalated body-centred cubic (b.c.c.) structures A6C60 (where A is K or Cs; ref. 4), a body-centred tetragonal structure for A6C60 (where A is K, Rb, Cs; ref. 5) and the superconducting, intercalated face-centred cubic (f.c.c.) material K3C60 (ref. 6). Here we report the preparation of a series of single-phase, isostructural f.c.c. superconductors with composition A3C60 (where A is K, Rb, Cs or a mixture of these), and show that Tcc increases monotonically with the size of the unit cell. Extended Hiickel band-structure calcula-tions also show a monotonic increase in the density of states at the Fermi level, N(EF), with lattice parameter. The primary impli-cation of these results is that all A3C60 superconductors have the same structure and that changes in Tc can be accounted for by changes in N(EF).
463 citations
TL;DR: It is argued that the assessment of the accuracy of the conduction-band states should rely mainly on the reproduction of major structures in the optical-absorption curves rather than on the size of the band gap.
Abstract: The electronic structures, the charge-density distribution, and the total energies of boron nitrides (BN) in the hexagonal, cubic, and wurtzite structures are studied by first-principles self-consistent local-density calculations. For the ground-state properties, the band structures, the equilibrium lattice constants, the bulk modulus and their derivatives, and the cohesive energy are in good agreement with other recent calculations and with experimental data. The relative stabilities and possible phase transitions among these three phases are discussed. The linear optical properties of these three crystals are also calculated and compared with the available measurements. For hexagonal BN, all the structures in the electron-energy-loss function as measured by inelastic electron scattering have been reproduced by the calculation. For cubic BN, the calculated dielectric functions is also in good agreement with the reflectance data. For wurtzite-structure BN, no optical data are available for comparison. These results are discussed in the context of crystal structure and bonding in these three crystals. Based on the analysis of the calculated and measured optical data on cubic and hexagonal BN, it is argued that the assessment of the accuracy of the conduction-band states should rely mainly on the reproduction of major structures in the optical-absorption curves rather than on the size of the band gap. The accuracy of the higher conduction-band states as calculated by the local-density theory is strongly energy and momentum dependent. Furthermore, a determination of the optical gap is complicated by the different roles of the direct and indirect transitions, and by the difficult task of extrapolating data to the low-frequency region.
389 citations
TL;DR: It is predicted that high frequency H2 modes acquire a width of about 20% of their frequency in superconductive fullerenes, and soften by about 5% compared to the insulating fullererenes.
Abstract: Intramolecular vibrations strongly scatter electrons near the Fermi-surface in doped fullerenes. A simple expression for the electron-phonon coupling parameters for this case is derived and evaluated by quantum-chemical calculations. The observed superconducting transition temperatures and their variation with lattice constants can be understood on this basis. To test the ideas and calculations presented here, we predict that high frequency H(2) modes acquire a width of about 20% of their frequency in superconductive fullerenes, and soften by about 5% compared to the insulating fullerenes.
382 citations
TL;DR: The atomic force microscope (AFM) was used to image an electrode surface at atomic resolution while the electrode was under potential control in a fluid electrolyte and revealed that the underpotential-deposited monolayer has different structures in different electrolytes.
Abstract: The atomic force microscope (AFM) was used to image an electrode surface at atomic resolution while the electrode was under potential control in a fluid electrolyte. A new level of subtlety was observed for each step of a complete electrochemical cycle that started with an Au(111) surface onto which bulk Cu was electrodeposited. The Cu was stripped down to an underpotential-deposited monolayer and finally returned to a bare Au(111) surface. The images revealed that the underpotential-deposited monolayer has different structures in different electrolytes. Specifically, for a perchloric acid electrolyte the Cu atoms are in a close-packed lattice with a spacing of 0.29 ± 0.02 nanometer (nm). For a sulfate electrolyte they are in a more open lattice with a spacing of 0.49 ± 0.02 nm. As the deposited Cu layer grew thicker, the Cu atoms converged to a (111)-oriented layer with a lattice spacing of 0.26 ± 0.02 nm for both electrolytes. A terrace pattern was observed during dissolution of bulk Cu. Images were obtained of an atomically resolved Cu monolayer in one region and an atomically resolved Au substrate in another in which a 30° rotation of the Cu monolayer lattice from the Au lattice is clearly visible.
342 citations
IBM1
TL;DR: In this paper, the electrical conductivity of PrNiO3 is shown to be metallic at room temperature, but undergoes a transition at 130 K to an insulating state, with a ∼ 0.2% contraction upon heating into the metallic state.
316 citations
TL;DR: In this paper, the first direct measurements of unit cell distortions and equation-of-state parameters of the orthorhombic perovskite as functions of composition and simultaneous high pressure and high temperature were obtained.
Abstract: High-pressure, high-temperature properties of MgSiO3, (Fe01Mg09)SiO3, and (Fe02Mg08)SiO3 perovskites have been investigated using a newly developed X ray diffraction technique involving monochromatic synchrotron radiation The first direct measurements of unit cell distortions and equation-of-state parameters of the orthorhombic perovskite as functions of composition and simultaneous high pressure and high temperature were obtained The experiments were conducted under hydrostatic pressure up to 30 GPa, into the stability field of the perovskite The results demonstrate that the perovskite is elastically anisotropic, with the lattice parameter b being 25% less compressible than a and c Under increasing pressures the orthorhombic perovskite is distorted further away from the ideal cubic structure in agreement with theoretical predictions The 298-K isothermal equations of state of the three perovskites are indistinguishable within the uncertainty limits of the experiment The zero-pressure bulk modulus KT0 = 261 (±4) GPa with its pressure derivative KT0′ = 4 is close to that determined in previous static high pressure measurements The thermal expansion obtained from the high P - T experiments are consistent with previous measurements carried out at zero pressure but shows a strong volume dependence The temperature derivative of the isothermal bulk modulus at constant pressure (∂KT/∂T)p is −63(±05)×10−2 GPa/K Analyses of the high-temperature data give a value for the Anderson-Gruneisen parameter δT of 65–75, which is significantly higher than that used in recent lower mantle models
307 citations
TL;DR: In this article, a new MBE growth method was proposed for InSb microcrystals on CdTe which has a nearly equal lattice constant to inSb. This method is based on the Sb incorporation into In droplets and thought to be useful for fabricating quantum well boxes.
306 citations
TL;DR: In this paper, the band gaps, band structure, and excited state (exciton) energies of CdS, GaAs, and GaP semiconductor clusters are calculated using pseudopotentials.
Abstract: The band gaps, band structure, and excited‐state (exciton) energies of CdS, GaAs, and GaP semiconductor clusters are calculated using pseudopotentials. In addition, the sensitivity of the exciton energies to the size, shape, crystal structure, and lattice constant of the unit cell are investigated. The calculated exciton energies of CdS clusters are in excellent agreement with experiment over a wide range of cluster sizes. Also, the exciton states of small CdS clusters are sensitive to whether their crystal structure is zinc blende or hexagonal. Such a sensitivity is absent in large CdS clusters. Furthermore, small GaAs clusters are shown to exhibit anomalous redshift of their absorption spectra, in sharp contrast to CdS and large GaAs clusters whose spectra always shift to blue with decreasing cluster size. Finally, the lowest‐energy non‐Franck–Condon transition in GaP clusters always shifts to blue with decreasing cluster size, whereas the higher‐energy Franck–Condon transition in small clusters exhibits the anomalous redshift. These novel findings reveal that (1) the optical spectroscopy of semiconductor clusters is strongly material and crystal structure dependent; (2) the spectroscopy of small clusters is dramatically different from those of large clusters and bulk; and (3) these effects cannot be explained, even qualitatively, using the effective‐mass approximation.
296 citations
TL;DR: Hard Ti x N and (Ti 1− x Al x )N films were prepared using the cathodic arc ion plating method as discussed by the authors, and they exhibited a cubic structure.
TL;DR: In this article, the crystal structures and cohesive energies for close-packed crystals of C_(60) and C_(70) were predicted using a force field developed recently for sp carbon atoms, and confirmed from calculations, that face-centred cubic packing is more stable than hexagonal close-packing (h.c.).
Abstract: Recent breakthroughs in synthesizing large amounts of C_(60), C_(70) and other fullerenes have made possible studies of the struc-tures and properties of fullerene crystals. Using a force field developed recently for sp carbon atoms, we predict here the crystal structures and cohesive energies for close-packed crystals of C_(60) and C_(70). We predict, and confirm from calculations, that for C_(60) face-centred cubic (f.c.c.) packing is more stable than hexagonal close-packing (h.c.p.), by 0.90 kcal mol−1, whereas for C70 h.c.p. is more stable than f.c.c. by 0.35 kcal mol^(−1). The cubic structure of C60 undergoes an orthorhombic distortion to space group Cmca at 0 K. At higher temperatures there is rapid reorientation (but not free rotation) of C_(60) molecules, suggesting that above about 200 K a phase transition occurs to an orientationally disordered, f.c.c. structure (with a room-temperature lattice parameter of 14.13 A). This may correspond to the first-order transition observed at 249 K. The threefold axes of the C_(60) molecules in the low-temperature structure are not aligned with the threefold crystallographic axes.
TL;DR: In this article, the bulk properties of cubic GaN/GaAs were investigated by cathodoluminescence, which revealed a broad midgap peak as well as several sharp emission peaks just below the expected band gap.
Abstract: We present the first comprehensive investigation of the bulk properties, both optical and structural, of cubic GaN as grown by plasma‐assisted molecular‐beam epitaxy on vicinal (100) GaAs substrates. X‐ray measurements determined the crystal structure of GaN/GaAs to be cubic with a lattice constant of 4.5 A. High resolution transmission electron microscopy revealed a high density of planar defects propagating along the GaN {111} planes. The majority of the defects originated from disordered regions at the GaN/GaAs interface. The optical properties of the films were investigated by cathodoluminescence which revealed a broad midgap peak as well as several sharp emission peaks just below the expected band gap. The data imply that the room temperature band gap of cubic GaN is approximately 3.45 eV.
TL;DR: Single-crystal x-ray diffraction methods were used to determine the crystal and molecular structure of C60 buckminsterfullerene, which is cubic, apparent Laue symmetry m3m, but it exhibits noncrystallographic systematic extinctions indicative of a twin in which I(hkl) and I(khl) are superimposed.
Abstract: Single-crystal x-ray diffraction methods were used to determine the crystal and molecular structure of C(60) buckminsterfullerene. At 110 kelvin C(60) is cubic, apparent Laue symmetry m3m, but it exhibits noncrystallographic systematic extinctions indicative of a twin in which I(hkl) and I(khl) are superimposed. In fact, C(60) crystallizes with four molecules in space group [See equation in the PDF file] of the cubic system (Laue symmetry m3) with lattice constant a = 14.052(5) angstroms (A) at 110 kelvin. The twin components are equal. A given component, which has crystallographically imposed symmetry [See equation in the PDF file] displays an ordered structure of a truncated icosahedron. The five independent C=C bonds that join C(6) rings average 1.355(9) A; the ten independent C-C bonds that join C(6) and C(5) rings average 1.467(21) A. The mean atom-to-atom diameter of the C(60) molecule is 7.065(3) A. The molecules are very tightly packed in the crystal structure, with intermolecular C...C distances as short as 3.131(7) A.
TL;DR: In this article, the fullpotential linear-muffin-tin-orbital method in combination with the local density functional theory is used to calculate the equilibrium lattice constant, the cohesive energy, the bulk modulus and its pressure derivative, the elastic constants, the Kleinman internal displacement parameter, the zone-center transverse-optical-phonon frequency, its Gruneisen parameter and the corresponding energy-band strain, and optical-mode deformation potentials of cubic SiC.
Abstract: The full-potential linear-muffin-tin-orbital method in combination with the local-density-functional theory is used to calculate the equilibrium lattice constant, the cohesive energy, the bulk modulus and its pressure derivative, the elastic constants, the Kleinman internal displacement parameter \ensuremath{\zeta} the zone-center transverse-optical-phonon frequency, its Gr\"uneisen parameter and the corresponding energy-band strain, and optical-mode deformation potentials of cubic SiC. The results for equilibrium properties and the transverse-optical phonon at the center of the Brillouin zone are shown to be in good agreement with the available experimental data and previous first-principles calculations. The elastic constants of 3C-SiC are transformed to a trigonal symmetry tensor along the 〈111〉 direction, which allows a comparison to experimental data on hexagonal SiC. The agreement is found to be good. The elastic constants are also shown to be in good agreement with experimental data on the Young's and shear moduli and the Poisson ratio for polycrystalline SiC and with the Young's modulus of 3C-SiC whiskers along the 〈111〉 direction, which is related to the theoretical cleavage strength. Predictions are also made for the deformation potentials, which have not yet been measured. The discrepancies with previous atomic-sphere-approximation calculations for the trigonal strain and optical-mode deformation potentials indicate the importance of nonspherical terms in the potential for these deformations. The absolute deformation potential of the valence-band maximum is computed by means of a heterojunction calculation between strained and unstrained materials. This procedure is shown to give good agreement with previous calculations for Si.
TL;DR: The binding energy, equilibrium lattice parameter, elastic constants and central zone phonon frequencies of Li2O, Na2O and K2O have been calculated at an ab initio level with CRYSTAL, a Hartree-Fock linear combination of atomic orbitals (LCAO) program for periodic compounds.
TL;DR: In this article, X-ray line profile measurements were performed on monocrystalline specimens of the γ-hardened nickel-base superalloy SSR 99 with axes close to the [001] direction.
Abstract: X-ray line profile measurements were performed on monocrystalline specimens of the γ′-hardened nickel-base superalloy SSR 99 with axes close to the [001] direction. The aim was to measure the local lattice parameters in the γ-matrix and in the γ′-particles and to obtain information on the lattice mismatch and internal stresses. For this purpose, a special high-resolution double crystal diffractomoter with negligible instrumental line broadening was used. Measurements were performed on specimens in the initial state with cuboidal γ′-particles and on creep-deformed specimens containing the so-called γ/γ′-raft structure. In several cases the line profiles were measured as a function of the rocking angle, and the intensity distributions were mapped in reciprocal space around the (002) and (020) Bragg reflections. In the undeformed state these intensity distributionsindicate that the local lattice parameter varies spatially in the γ-phase. The line profiles of specimens in the initial state were asymmetric. A remarkable result obtained on creep-deformed specimes was that, whereas the asymmetry of the (020) line profiles was enhanced to the extent that a hump or a second peak appeared, the asymmetry of the (002) line profiles was reversed in sign. A quantitative evaluation yielded mean values of the constrained lattice mismatch which, in the case of creep-deformed specimens, differ significantly for the (001) and (010) lattice plane spacings. It is concluded that the orientation-dependent lattice spacings represent a triaxial state of residual stress which has its origin in the superposition of the originally present coherency stresses and the deformation-induced internal stresses. All observed features could be explained in detail in terms of a composite model of plastic deformation, which takes into account the dislocation networks deposited at the γ/γ′-interfaces during deformation.
TL;DR: In this article, the packing and thermal motion of the terminal CH3 groups of monolayers of nalkane thiols self-assembled on Au(111)/mica films and a single crystal surface was studied.
Abstract: Low energy helium diffraction has been used to study the packing and thermal motion of the terminal CH3 groups of monolayers of n‐alkane thiols self‐assembled on Au(111)/mica films and a Au(111) single crystal surface. At low temperatures (<100 K), the terminal CH3 groups are arranged in domains containing a hexagonal lattice with a lattice constant of 5.01 A. As the length of the carbon chain is shortened, an abrupt decrease in the diffraction peak intensities is observed for CH3(CH2)9SH/Au(111)/mica, and no diffraction is observed for CH3(CH2)5SH/Au(111)/mica. This is indicative of a sudden decrease in surface order at around ten carbon atoms per chain. A semi‐quantitative estimation of the average domain size of each monolayer surface shows a maximum of 46 A at intermediate chain length [CH3(CH2)13SH/Au(111)/mica], decreasing to 26 A at longer [CH3(CH2)21SH/Au(111)/mica] and 41 A at shorter [CH3(CH2)9SH/Au(111)/mica] chain lengths. No phase transitions could be detected at the surfaces of these monolay...
TL;DR: In this article, the authors used factor group analysis and correlating the bands by their intensities to assign the SiO4 internal motions, as a rotation, or to a type of translation.
Abstract: Infrared reflectance (IR) and Raman spectra were collected on small (ca. 500 micron) single crystals of 5 natural garnets with nearly end-member compositions: pyrope (98% Mg3Al2Si3O12), almandine (83% Fe3Al2Si3O12), spessartine (98% Mn3Al2Si3O12), grossular (97% Ca3Al2Si3O12), and andradite (99% Ca3Fe2Si3O12). Frequencies and symmetry assignments were determined for all 17 IR modes and all 25 Raman modes. By using factor group analysis and by correlating the bands by their intensities, bands were assigned to either one of the SiO4 internal motions, as a rotation, or to a type of translation. The assignments are supported by (1) the distinct trends of frequencies with cell size and cation masses for each of the different types of motion, (2) the similarity of garnet energies for each of the different types of motion to those of olivine with the same cation, and (3) the closeness of the T1u IR frequencies to the T2g Raman frequencies. Mode mixing appears to be weak. Correlations between frequencies and structural parameters suggests a direct dependence of force constants on lattice parameter. This relationship arises from bond lengths in the garnet structure being constrained by the size and compressibility of adjacent polyhedra through edge-sharing. Comparison of our endmember data with previous powder IR studies of intermediate garnets indicates that dodecahedral (X) and octahedral (Y) sites alone exhibit two-mode behavior for those solid solutions involving two ions with considerably different masses. However, for solid solutions involving cations of much different ionic radii, two-mode behavior is found for the translations of SiO4 groups. This is the first report of two-mode behavior that is unrelated to mass, and instead is due to significantly different force constants in the pyralspites compared to the ugrandites.
TL;DR: In this article, the first experimental study of the molecular structure of the self-assembled monolayer of CH 3 (CH 2 ) 17 SH formed on the Ag(111) surface was described.
Abstract: We describe the first experimental study of the molecular structure of the self-assembled monolayer of CH 3 (CH 2 ) 17 SH formed on the Ag(111) surface. Using both low-energy He diffraction and grazing incidence X-ray diffraction, we show that the monolayer formed on Ag is both incommensurate and rotated with respect to the Ag lattice, with a lattice spacing which is very similar to n-alkane chains in bulk hydrocarbon crystals.
TL;DR: In this article, an indirect band gap Γv25' → Δc1 was found for the new semiconductor Si1−x−yGexCy over most compositions x and y.
Abstract: Single‐crystal alloys of diamond with Si and Ge are investigated theoretically. An indirect band gap Γv25’ → Δc1 is found for the new semiconductor Si1−x−yGexCy over most compositions x and y, with an indirect Γv25’ → Lc1 gap found for the remaining compositions. The estimated band gaps span the 0.62–5.5‐eV‐range. Predictions are made for band gap versus lattice parameter in the new alloy semiconductors Si1−xCx and Ge1−xCx.
25 Mar 1991-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this paper, the crystal to non-equilibrium phase transition induced by ball-milling has been evidenced in the CuW system, which exhibits a total immiscibility in both solid and liquid states.
Abstract: For the first time, based on X-ray diffraction, scanning electron microscopy/energy dispersion X-ray analyses, differential thermal analysis and differential scanning calorimetry experiments, the crystal to non-equilibrium phase transition induced by ball-milling has been evidenced in the CuW system. This system exhibits a total immiscibility in both solid and liquid states. Starting from elemental copper and tungsten powders, a partial solubility of copper into the cubic tungsten lattice as well as of tungsten into the f.c.c. copper lattice is induced by ball-milling. Such an enhancement of the solubility is revealed by an effect on the lattice parameter of both Cu(W) and W(Cu) crystalline solid solutions over the whole investigated composition range, i.e. Cu 5 W 95 to Cu 95 W 5 (wt.%). Such an experimental investigation of the crystal to amorphous phase transition induced by ball-milling in a system which exhibits a positive heat of mixing either in the solid or in the liquid states supports our previous results leading to the conclusion that the mechanisms of the phase transitions induced by ball-milling are different from those of the so-called classical solid-state amorphization.
TL;DR: This simple method is tested via predictions of surface energies, surface reconstructions, and bulk distortions of metals and semiconductors and good agreement is obtained with the results of both experiment and first-principles calculations.
Abstract: A method is proposed for computing material defect and surface properties accurately at the atomic level The method is both simple and accurate and treats both semiconductors and metals Lattice defect and surface energies are determined via perturbation theory on a crystal whose lattice constant is chosen to minimize the perturbation The energy of the equivalent crystal as a function of its lattice constant is given by a universal energy relation This simple method is tested via predictions of surface energies, surface reconstructions, and bulk distortions of metals and semiconductors Good agreement is obtained with the results of both experiment and first-principles calculations
TL;DR: In this article, a thin film of 4-5 layers of NiO(100) is built up on the surface of a NiO surface exposing terraces of approximately 100 A width which are separated from each other by monatomic steps descending along the [010] direction.
TL;DR: In this paper, a systematic study of the change in structural quality of as-grown GaAs layers deposited at temperatures between 180 and 210°C by molecular beam epitaxy was performed using transmission electron microscopy, double-crystal x-ray rocking curves, and particle-induced x−ray emission.
Abstract: A systematic study of the change in structural quality of as‐grown GaAs layers deposited at temperatures between 180 and 210 °C by molecular beam epitaxy was performed using transmission electron microscopy, double‐crystal x‐ray rocking curves, and particle‐induced x‐ray emission. We found that the crystal quality was correlated strongly with growth temperature near 200 °C. The lattice parameter and the amount of As incorporated in the layer were observed to increase at lower growth temperatures. After exceeding a certain growth‐temperature‐dependent layer thickness, large densities of pyramidal‐type defects are formed, which at lowest growth temperature result in the breakdown of crystallinity and in columnar polycrystalline growth. The lattice expansion is ascribed to the excess As in the layers. The mechanisms of breakdown of crystallinity are discussed.
TL;DR: On rapporte la croissance des films de nitrure de bore sur les faces (001) du silicium en utilisant la methode de l'ablation laser excimer pulse, est zinc-blende cubique en transmission.
Abstract: We report the growth of boron nitride films on (001) faces of silicon using the method of pulsed-excimer-laser ablation The structure of the deposited films is cubic zinc blende with a lattice constant of 3619 \AA{} The films were found to be heteroepitaxial with the cubic BN〈100〉 axes parallel to Si〈100〉, as characterized by x-ray diffraction and high-resolution transmission electron microscopy We find evidence for an unusual 3:2 commensurate lattice matching
TL;DR: A series of LiNbO3 crystals were grown with different Li/Nb ratios and a MgO doping up to 8 mol%. The lattice constants, the permittivities, the elastic compliances, the piezoelectric constants, birefringence and the pyroelectric coefficient were measured and correlated to the Li2O content or to the Mg O content of the crystals respectively as mentioned in this paper.
TL;DR: The microstructure of Fe73.5Si13.5B9Nb3Cu1 soft magnetic material with a nanocrystalline structure has been investigated by atom probe field ion microscopy.
Abstract: The microstructure of Fe73.5Si13.5B9Nb3Cu1 soft magnetic material with a nanocrystalline structure has been investigated by atom probe field ion microscopy. In the as‐quenched amorphous sample, all the alloying elements were found to distribute homogeneously as an amorphous solid solution. In the annealed sample with the optimum soft magnetic properties, we found that two phases were present. One was Fe‐Si solid solution and the other was the B‐ and Nb‐enriched region with less Si content. Although some uncertainty remains regarding Cu, the present result is consistent with an early speculation based on the lattice parameter measurement.