Deconvolution method for composition profiling by Auger sputtering technique

Some of the sputter broadening effects on profile measurements using the Auger sputtering technique have been quantitatively investigated for $\text{Ag}\text{Au}$ and $\text{Cu}\text{Ni}$ systems. Two methods have been used to measure the resolution function as a function of the sputter distance for these two systems. The broadening can be separated into contributions from original surface roughness and sputtering effects, the latter amounting to about 7% of the sputter depth for $\text{Cu}\text{Ni}$ and 14% for $\text{Ag}\text{Au}$ interfaces. Based on the measured resolution function, a deconvolution method has been developed to facilitate the retrieval of the actual profile from the observed profile by reducing the sputter broadening. Using this method, we found that the measured interfacial profile can be substantially sharpened. The implications of using the deconvolution method for interdiffisuion studies in thin films are discussed.     

Experimental susceptibility of CuFe, AgFe and MoFe and the results of the Wilson theory

The low temperature susceptibility of the local moment system $\text{Mo}$Fe has been measured by the Mössbauer effect. The susceptibility for this system and for the system $\text{Cu}$Fe, $\text{Ag}$Fe and $\text{Au}$Fe show general agreement with the prediction of the Wilson theory.     

Polymorphism in skinnerite,Cu3SbS3

Phase transitions in Cu₃SbS₃ are investigated under temperature variation using X-ray diffraction and nuclear quadrupole resonance. Below 263 K, Cu₃SbS₃ has the same structure as Wittichenite, the low temperature form of Cu₃BiS₃, space group P 2₁2₁2₁. Between 263 and 395 K it is monoclinic, space group P $\text{2}{}_1\text{c}$, and above 395 K it is orthorhombic, space, group Pnma with the high temperature Cu₃BiS₃ structure. At 295 K, Cu₃SbSe₃ has the orthorhombic space group Pnma with unit cell parameters $\text{a}\text{= 7.97}$, $\text{b}\text{= 10.61}$ and $\text{c}\text{= 6.83}\text{A}\text{?}$.     

Interpretation of a new feature in photoemission from Cu based alloys with polyvalent solutes

In our recent angle resolved photoemission studies of oriented single crystal surface of $\text{Cu}$Al and $\text{Cu}$Ge solid solutions we had found a new structure lying between 4 and 5 eV below the Fermi energy, which could not be related to either the bulk or the surface states in the random alloy. To understand its nature and origin we report and discuss photoemission measurements from Cu films, submonolayer to a monolayer thick, deposited on the Al(111) and $\text{Cu}\text{Al(111)(}\text{3}\text{×}\text{3}\text{R}\text{30°)}$ alloy surfaces and from Al and Zn alloys containing dilute Cu impurities. Some experiments on the (100) surfaces in the various cases were also carried out. On the basis of these results, we suggest that the aforementioned new photoemission feature is characteristic of Cu clusters and isolated Cu impurities in polyvalent impurity-rich environment. These clusters probably lie at the topmost layer of the $\text{Cu}$Al and $\text{Cu}$Ge alloy surfaces.     

Spin relaxation rates in CuFe measured by neutron scattering

The absolute value and the temperature dependence of the spin relaxation rate of the Kondo system $\text{Cu}$Fe has been deduced from the magnetic scattering of unpolarized neutrons with energy analysis.     

An anharmonic force field for SO3

An anharmonic force field for SO₃ based on the valence force model has been investigated. The results of extending the model to include some further estimated cubic interaction potential constants have also been investigated. The phenomenological parameters calculated from both model force fields agree with those few values which have been experimentally determined. A calculation of the inertia defect has been made, and thus the value of C₀ has been determined. The equilibrium structure has been determined to be: $\text{r}{}_{\mathrm{e}}\text{= 1.4184 ± 0.0010}\text{A}\text{?}$.     

Paramagnetic curie temperature in dilute magnetic alloys: Influence of order-disorder transitions

The influence of order-disorder transitions upon the paramagnetic Curie temperature, θ, of alloys with dilute concentrations of Mn has been measured. (Cu_0.83Pd_0.17)_1-cMn_c in the ordered state yields results very similar to those for $\text{Cu}$Mn with one striking exception. The sign of the contribution to θ which is linearly dependent upon Mn concentration is reversed. This sign reversal has serious implications for any model of RKKY coupling between impurities and several possibilities are discussed.     

Electron drag of dislocations in thin metal plates

The electron force dragging dislocations in a thin metal plate of thickness d has been calculated and the dependence of the drag force F on the parameter $\text{d}\text{l}$ (l is the electron free path length) determined for the cases $\text{d}\text{l ? 1}$ and $\text{d}\text{l ? 1}$. With d ? l, the drag force depends upon the nature of electron scattering on the plate surface. The drag force dependence on the sample size has also been considered for a d.c. magnetic field H parallel to the plate faces. In the case of diffuse scattering the second derivative of F(H) reveals a square root singularity at the value of the magnetic field where the electron orbit diameter is equal to the plate thickness.     

Hall effect in dilute magnetic alloys

We review the theory and the experimental results on the Hall effect in noble metals containing magnetic impurities of transition metals. In order to illustrate the various types of observed effects, we focus succesively on selected systems: $\text{Cu}$Mn, with only enhancement of the ordinary Hall effect due to the existance of different spin-up and spin-down currents; $\text{Au}$Fe and $\text{Au}$Cr, with skew scattering by magnetic impurities; $\text{Cu}$MnT ternary alloys (where T is a non-magnetic impurity), with skew scattering effects due to combined spin—orbit scattering by non-magnetic impurities and spin scattering by Mn impurities. The skew scattering in $\text{Au}$Fe and $\text{Au}$Cr can be ascribed to the orbital character of the impurity moments and accounted for in an orbitally degenerate virtual bound state model. However, the anomalous temperature dependence of the skew scattering in Kondo alloys at low temperature is not well understood. We also present some magnetoresistance data in order to describe the links between the Hall effect and the magnetoresistance in magnetic alloys. In particular, we relate the skew scattering and the magnetoresistance anisotropy observed in $\text{Au}$Cr alloys.     

Magnetoelastic effects in dilute magnetic alloys

Ultrasonic studies of $\text{Cu}$Mn, $\text{Au}$Mn and $\text{Au}$Fe alloys where the concentrations of the transition metal ranges between 1 and 10% show that the longitudinal sound velocity has a marked field dependence at temperatures below the peak in the magnetic susceptibility and a negligible field dependence above it. This suggests that there may be an ordered magnetic state in these alloys.     

Search for baryonium production in pp and K−p interactions at 12 GeV

A search has been made for narrow structures in $\text{p}$p, $\text{p}$pπ^? and Λ⁰$\text{p}$ systems. No significant structures are seen. The upper limit at the 99.5% confidence level for production of narrow states in the $\text{p}$p system in the mass range 2.0–2.2 GeV is 40 nb.     

Coriolis constants of spherical-top molecules from low-temperature infrared studies of vapor band contours: Application to the force field of tungsten hexafluoride

The infrared-active stretching fundamental ν₃ of WF₆ vapor has been studied over the temperature range T = 190–310 K. At lower temperatures the hot-band structure is sufficiently suppressed to allow accurate measurements of the P-R branch spacing, which is a linear function of $\text{T}{}^{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$. From the slope of a least-squares line fitting 36 measured spacings, the Coriolis constant is found to be ζ₃ = 0.123. Enough overtone and combination bands have been observed in the infrared and laser Raman spectra of WF₆ for harmonic fundamental frequencies to be estimated. Harmonic force constants are calculated, using ζ₃ as the necessary additional constraint in the F_1u symmetry block. Possible sources of error are discussed and error limits are estimated for all reported frequencies and force constants. The valence stretching force constant is ${}_{\mathrm{r}}\text{= 5.50 ± 0.07}\text{mdyn/}\text{A}\text{?}$.     

ESR aspects of the Mn2+−Cu2+ coupled pair

Recent ESR experimental data on Mn²⁺?Cu²⁺ pairs, obtained by doping with manganese the dimeric Cu (pyridine N-oxide) Cl₂·.H₂O complex, are interpreted by means of a strong isotropic exchange model. Theg values of the pair and the hyperfine constants at the manganese and copper nuclei, for the observed effective spin S = 2, are given by the relations

$\text{g =}\text{7}\text{6}\text{g}{}_{\mathrm{Mn}}\text{?}\text{1}\text{6}\text{g}{}_{\mathrm{Cu}}$

,

$\text{A}\text{?}{}_{\mathrm{Mn}}\text{=}\text{7}\text{6}\text{A}{}_{\mathrm{Mn}}\text{,}\text{A}\text{?}{}_{\mathrm{Cu}}\text{= ?}\text{1}\text{6}\text{A}{}_{\mathrm{Cu}}$

, where g_Mn, g_Cu,A_Mn and A_Cu are the characteristic single-ion values for the quoted constants. The antiferromagnetic coupling between the Mn²⁺ spin $\text{(}\text{5}\text{2}\text{)}$ and the Cu²⁺ spin $\text{(}\text{1}\text{2}\text{)}$ is responsible for the observed g values, all measurably lower than the free electron value. Also to be noted are the enhancement of the hyperfine constant at the manganese nucleus, and the curious change of sign for that at the copper nucleus.     

Flux peaking of channeled ions in interstitial compounds NbO and ZrO13

A double flux peaking has been observed in a planar channeling of a NbO single crystal, while a single peak has been seen on a $\text{ZrO}{}_{\mathrm{<mtext>1</mtext><mtext>3</mtext>}}$ crystal. The experimental results are compared with an analytical calculation based on the continuum model.     

Superconductivity and crystal structure of ternary CuxMo3S4 compounds with 0 ≤ x ≤ 1 prepared by anodic oxidation of Cu1.0Mo3S4

Superconductivity and crystal structure data are reported for a series of ternary Cu_xMo₃S₄ samples with 0 ≤ x ≤ 1 which were prepared by anodic oxidation of Cu_1.0Mo₃S₄. A phase with the composition Cu_0.5Mo₃S₄ was found to have rhombohedral lattice parameters $\text{a}{}_{\mathrm{R}}\text{= 6.447(5)}\text{A}\text{?}$ and α_R = 93.74(4) ° and a superconducting critical temperature T_c = 5.8 K. The dependence of T_c on pressure for Cu_0.5Mo₃S₄ has been measured between 0 and 19 kbar.     

Search for new flavour production at PETRA

The topological distribution of hadrons from the reaction e⁺e^?→multihadrons has been studied at PETRA energies between $\text{s}\text{=22}\text{and}\text{31.6 GeV}$. No evidence is seen for spherical events which would be expected if massive particles bearing new flavours were produced.     

Excited vibrational state microwave spectra,structure, and force-field of trifluorosilane

The J = 2?1 microwave spectrum of six isotopic species of HSiF₃ has been observed and assigned in excited states of five of the six fundamental vibrations. The assignment is based on relative intensities, double resonance experiments, and trial anharmonic force constant calculations. Analysis of the spectra leads to experimental values for five of the $\text{α}{}_{\mathrm{r}}{}^{\mathrm{B}}$ constants, all three l-doubling constants q_t, one Fermi resonance constant φ₂₃₃, and one zeta constant $\text{ζ}{}_{\mathrm{6,\; 6}}{}^{\mathrm{(z)}}$.The harmonic force field has been refined to all the available data on vibration wavenumbers, centrifugal distortion constants, and zeta constants. The cubic anharmonic force field has been refined to the data on $\text{α}{}_{\mathrm{r}}{}^{\mathrm{B}}$ and q_t constants, using two models: a valence force model with two cubic force constants for SiH and SiF stretching, and a more sophisticated model. With the help of these calculations, the following equilibrium structure has been determined: $\text{r}{}_{\mathrm{e}}\text{(}\text{SiH}\text{) = 1.4468(±5)}\text{A}\text{?}$, $\text{r}{}_{\mathrm{e}}\text{(}\text{SiF}\text{) = 1.5624(±1)}\text{A}\text{?}$, ∠HSiF = 110.64(±3)°,     

Classical many-body model for heavy-ion collisions incorporating the Pauli principle

A classical model for heavy-ion collisions, introduced previously, has been extended to include certain effects of the Pauli principle. All nucleons are treated equally. They obey classical dynamics and interact through an ordinary two-body force and through a momentumdependent two-body “Pauli core” which satisfies, approximately, that $\text{p}{}_{\mathrm{ij}}\text{r}{}_{\mathrm{ij}}\text{≧ξ}\text{h}\text{?}$, where ξ is a dimensionless constant. A form for the Pauli core is presented. The ordinary two-body force has been adjusted to fit bulk properties of nuclei and to reproduce that moment of nucleon nucleon scattering cross sections which is relevant to hydrodynamics. The parameters of the forces are given.     

Reduction of the Kondo temperature in low temperature deposited alloy films of CuFe

The low temperature resistance anomaly has been investigated in highly disordered $\text{Cu}$Fe films (50–200 ppm) after quench condensation and after annealing of the films at different temperatures, which reduces the degree of disorder. An analysis of the data shows that with respect to the films annealed at room temperature and to bulk samples the Kondo temperature of a disordered film is reduced by a factor of two.     

Dynamic behaviour of planar dislocation pile-ups

The dynamic behaviour of a twin and a slip band is considered when simulated as the planar pile-ups of partial and complete dislocations, respectively, with a continuum distribution density. A similarity between solutions has been found for the equations describing the twin shrinking under the action of surface tension forces, and the slip band growth under the action of a δ-function type force. It turns out that the twin length decreases according to the law $\text{L～ (τ ? t)}{}^{\mathrm{<mtext>2</mtext><mtext>3</mtext>}}$, where τ is the full time of the twin shrinking. It has been also shown that within a small region directly adjacent to the twin center the dislocation density increases according to the law $\text{1}\text{x}$, where x is the distance to the center. Annihilation of opposite-sign dislocations takes place in the twin center where the twin cannot be considered planar and where a two-dimensional region is formed. An attempt has been made to describe this region and its evolution in the process of the twin shrinking. The theoretical results obtained are in good agreement with the experimental data for the process of elastic twin shrinking and sound emission arising in this case.