Abstract The effect of neutron irradiation and subsequent recovery has been studied for NbO single crystals a defective NaCl structure containing 25% vacancies niobium oxygen. A very large increase (about 1%) in the lattice constant is observed after 1.5 × 1019 1 1020 nvt (> MeV). From intensity measurements x-ray diffraction, it revealed that knock-on atoms fill preferentially their respective vacant sites; Mb occupy Nb-vacancies, O O-vacancies with nearly same probabilities; 0.53 nvt. mean...

Highly nitrogenated amorphous carbon films have been prepared by reactive rf-magnetron sputtering using pure N 2 or Ar/N mixed gases. The nitrogen content measured Rutherford backscattering spectrometry was 40 at% for gas and 35 Ar75%-N 25% gas. Oxygen atoms of about 7 were also detected. Infrared spectra showed a broad absorption band in the range from 1200 to 1600 cm -1 assigned incorporated bonding network carbon. They an near 2200 C≡N N=C=O bond, but no trace N-H C-H bond seen.

The crystal structure of interstitial solid solution zirconium-oxygen system was investigated by means X -ray, electron and neutron diffraction on specimens in the composition range between 11 27 at% 0. were prepared melting appropriate mixtures zirconium metal dioxide an arc-furnace. In addition to a superstructure found Holmberg Dagerhamn ZrO y (0.33< <0.40), new having different ordered arrangement oxygen x (0.25< <0.33). atomic these superstructures can be expressed terms stacking...

The crystal structure of the interstitial solid solution alpha titanium-oxygen system has been investigated by a combined method electron, neutron and X-ray diffraction as functions composition annealing temperature. existence two-types superstructure established over nearly whole range below critical One them designated α' layer-ordered anti-Cd(OH) 2 type (space group P \bar3 m 1) involving out-of-steps with regard to oxygen distribution. other is low-temperature form α'' which trigonal...

Interstitial order-disorder transformation regarding oxygen atoms dissolved in alpha-titanium has been studied by neutron diffraction on single crystals the range from 17 to 28 at% O. Occupation probabilities of octahedral interstitial sites are determined quantitatively with variation composition and temperature. The change long-range order increasing temperature reveals a two-step process attributed disordering atoms. static displacement titanium parallel c -axis increases almost linearly...

It has been confirmed by electron diffraction that anti-phase domains in Cu 3 Au giving rise to diffuse superlattice reflections grow up during isothermal annealing below the transition temperature of order-disorder, evaporated films nearly stoichiometric compositions being used. This fact means are not an equilibrium state unlike so-called periodic structure. Electron-microscopic images domain boundaries alloy with 26 atomic per cent gold have observed. These also confirm growth domains....

Interdiffusion and interfacial reaction between a sputter-deposited YBa2Cu3Ox thin film substrates (MgO, sapphire, quartz, Si) have been investigated by 2.7 MeV 4He+ Rutherford backscattering spectrometry. The diffusivities of Cu in the substrate elements (Mg, Al, Y-Ba-Cu-O films determined over annealing temperature range from 876 to 1226 K an oxygen atmosphere. Among three metallic Y, Ba, Cu, diffuses fastest into substrates. Copper silicide is observed region Si substrate. these...

The very early stage as well late of phase separation process in FeCr alloys (Fe-20, 30, 40, 60 at%Cr) have been studied by pulsed cold neutron small angle scattering instrument (SAN). At the stage, intensity I ( q ) obeys -2 dependence at high side function. results are accord with theory Langer et al. which takes into account nonlinear and thermal fluctuations effects. where shows -4 dependence, a dynamical scaling law holds, while it is not case for earlier stage. Phase diagram system...

A new ordered structure of Au5Sn is determined by X-ray and electron diffraction using single crystals. The unit cell the hexagonal superstructure contains 15 Au 3 Sn atoms, having lattice constants a=\sqrt3 a0 c=3 c0, where a0∼2.94 Å c0∼4.78 are those fundamental hcp cell. closest interatomic distance Sn–Sn pairs \sqrt3 a0∼5.1 Å, displacement gold atoms from ideal close packing evaluated as 0.037 Å. phase transforms to disordered (ζ) at 195°C, a revised diagram region 10–20 at% proposed.

Neutron diffraction experiments have been made to reveal the nature of interstitial order-disorder transformation in ZrO system using single crystals. The disordering transition alloy with O/Zr ⪅ 0.3 occurs below 450 °C, while composition = 0.4 undergoes stepwise such a way that stacking sequence oxygen-atom layers changes 600 °C and subsequently ordered distribution becomes random. A tentative phase diagram is proposed on basis present results. Neutronen-Beugungsversuche wurden zur Klärung...

The crystal structure and the phase transformation of cobalt alloys containing less than 8 at% Fe have been investigated by means X-ray diffraction, electron microscopy heat capacity measurements. A double hcp α-La type is found in range 1.5 to 4.8 at room temperature 0.7 0.9 transform from through dhcp fcc with increasing temperature. stacking fault energy 2 estimated be about 18 erg/cm microscopic observation extended dislocation nodes, this value agrees well an evaluation calorimetric data.

Ordered arrangements of oxygen atoms dissolved in α-zirconium near the stoichiometric composition ZrO1/3 have been investigated by means electron diffraction and dark-field microscopy. The are specified as long period stacking sequences interstitial layers octahedral sites normal to c axis h.c.p. lattice. Eight kinds variants found range from 24 26 at.% O order 8H (7\overline 1), 5H (4\overline 12R (3\overline 1)3, 7H 12\overline 10H (1\overline 31\overline 13\overline 9R (2\overline 12H...

Crystal structure and phase transition in the hafnium-oxygen system containing 10-20 at% O have been studied by means of electron, neutron X-ray diffraction calorimetry as well. The oxygen atoms occupy octahedral holes h.c.p. metal lattice two types interstitial superstructures are found at hypo- hyper-stoichiometric composition HfO 1/6- 1/6+ below 430°C. constants hexagonal supercells respectively \(a{=}\sqrt{3}a_{0}\), c =3 0 =2 , where a ∼3.2Å ∼5.1Å those lattice. sublattices described...

Charge state dependences of positron trapping rates associated with divacancies and vacancy-phosphorus pairs in Si have been studied by controlling the Fermi level systematically. The specific both a divacancy pair increase an negative charge on them. A positively charged shows no detectable trapping. Such clearly show that long-range Coulomb interactions between or play important role process.

Diffuse scattering due to the atomic short range order in Cu-20∼28 at % Mn single crystals has been studied by time of flight measurement pulsed neutrons. The SRO parameters α j 25% alloy were obtained analyzing diffuse intensity, and used for a computer simulation configuration. local arrangements show preference no manganese atom pairs as first neighbors two second neighbors, which tends satisfy Ni 4 Mo-like structure. ratios pairwise interactions are evaluated discussed briefly.