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1.
K. P. Meletov A. A. Maksimov I. I. Tartakovskii 《Journal of Experimental and Theoretical Physics》1997,84(1):144-150
Measurements have been made of the Raman, optical absorption, and luminescence spectra of single crystals and pellets of the
fullerite C70 at T=300 K and at pressures up to 12 GPa. The baric shift dω/dP and the Grüneisen parameters of the Raman-active intramolecular phonon modes have been determined. It has been established
that the d
ω/dP value for certain phonon modes abruptly changes at pressures of P
1≈2 GPa and P
2≈5.5 GPa, as do the half-widths of the Raman lines. These features in the Raman spectrum are associated with phase transitions
at high pressure. The baric shifts of the absorption and luminescence edges of C70 crystals have been determined and are −0.12 eV/GPa and −0.11 eV/GPa, respectively, for absorption and luminescence. The baric
shift of the absorption edge decreases significantly with increasing pressure and is −0.03 eV/GPa at 10 GPa. These data have
been used to determine the deformation potential of the fullerite C70, which is about 2.1±0.1 eV.
Zh. éksp. Teor. Fiz. 111, 262–273 (January 1997) 相似文献
2.
《光谱学快报》2013,46(6):633-641
Abstract X‐ray photoelectron spectroscopy (XPS) has been used for the first time to study the composition of calcium oxalate (CaOxa) stones and uric acid stones. This technique allows for the identification and location of various inorganic and organic species at the same time. In CaOxa stones, there were less than 10% of phosphates. Sectional analyses of these stones indicated that the content of phosphorus in the stone center is higher than that in stone crust. In uric acid stones, CaOxa was rarely found. XPS is able to detect differences in chemical functionality. In uric acid stones, the binding energy (E b) for nitrogen atoms were about 399.5 ± 0.2 eV, which are largely characteristic of organic nitrogens N (?3). In comparison, the E b values of N (+5) in inorganic compounds are about 401 eV. 相似文献
3.
The kinetics of silicon interaction with textured tantalum ribbons having a predominantly (100)-oriented surface has been
studied by Auger electron spectroscopy. For T<700 K, silicon builds up on the surface. Within the 900<T<1000-K interval, after the formation of a monolayer coating, the excess silicon enters into layer-by-layer growth of the
silicide TaSi2. Within 1150<T<1320 K, this excess silicon reacts with tantalum to produce in a layer-by-layer manner the Ta5Si3 silicide; this compound is unstable and decomposes for T>1320 K to form Ta 4Si, with only one third of the original silicon monolayer being left on the surface. The activation energy of Ta5Si3 decomposition is 4.3±0.2 eV. The activation energy of Si thermal desorption at low coverages is 5.4±0.2 eV.
Fiz. Tverd. Tela (St. Petersburg) 39, 1484–1490 (August 1997) 相似文献
4.
The shifts and shapes of ArL 3 Auger lines due to the post-collision interaction (PCI) in the inner-shell ionisation of theL 3-shell of argon by electron impact have been measured for the range of excess energiesE 1=10 to 1,500 eV. The experimental shifts {ie67-01} could be fitted by a relation {ie67-02} withc=(5.3±0.4) andn= (?0.45±0.04) whereГ(ArL 3)=130 meV is the ArL 3-level width. In a classical model the PCI shifts have been calculated for two limiting cases:a) whereE 1 is large enough (E 1>50 eV) for the motion of the two slow electrons to be treated as uncorrelated, andb) forE 1→0. The calculated shifts forE 1=250, 750 and 1,750 eV are in good agreement with the experimental results. Also the calculated PCI distorted shapes of Auger lines for differentE 1 agree reasonably with the experimental Auger line shapes. 相似文献
5.
A. N. Zhiganov A. Ya. Kupryazhkin R. R. Mulyukov I. Kh. Bitkulov 《Technical Physics》2002,47(11):1440-1443
By the method of helium thermal desorption from submicrocrystalline palladium presaturated in the gaseous phase, the diffusion coefficient D eff and solubility coefficient C eff of helium are measured in the range P=0–3 MPa and T=293–508 K. The pressure dependence of C eff flattens at high pressures. At low saturation pressures, the temperature dependences of the diffusion and solubility coefficients may be divided into (1) high-temperature (400–508 K) and (2) low-temperature (293–400 K) ranges described by the exponentials D 1, 2=D 0exp (−E 1, 2 D /kT) and C 1, 2=C 0exp (−E 1, 2 S /kT). The energies of diffusion activation are E 2 D =0.0036±0.0015 eV and E 1 D =0.33±0.03 eV, and the solution energies are E 2 S =−0.025±0.008 eV and E 1 S =0.086±0.008 eV in the low-and high-temperature ranges, respectively. Mechanisms behind the diffusion and solution of helium are discussed. 相似文献
6.
Thermoreflectance measurements of the energies E0, Δ0 and E1 have been made throughout the composition range of ZnS-Te alloys. The bowing parameters were found to be 2.8 ± 0.2 eV for the E0 gap, 0.48 ± 0.08 eV for Δ0 and 1.5 ± 0.2 eV for the E1 energy-gap. These measured bowing parameters are in good agreement with the values calculated from EPM theory. 相似文献
7.
A. A. Skvortsov A. M. Orlov L. I. Gonchar 《Journal of Experimental and Theoretical Physics》2001,93(1):117-120
The magnetoplastic effect in dislocation silicon is discovered. It is shown that in the presence of tensile stresses (up to 20 MPa), the mechanically activated path of surface dislocation half-loops is limited mainly by the dynamics of defects in various slip systems relative to the applied load. The activation barriers for the motion of dislocations controlled by various conditions in the temperature range T=850–950 K are E aF=2.1±0.1 eV and E aS=1.8±0.1 eV. An increase in the path of surface dislocation half-loops and a change in the activation barriers are detected (E aF=1.4±0.1 eV and E aS=1.6±0.1 eV) after subjecting silicon to a magnetic field (B=0.7 T) for 30 min. Possible reasons behind the observed effects are discussed. 相似文献
8.
Abstract The energy shift of the He 11S0?21P1 transition, ΔE(n), can be used to determine the density, n, of He in bubbles in metals. A self-consistent band structure calculation for solid fcc He yields a linear relationship ΔE=C.n with C th=22 × 10?3 eV nm3. Systematic electron energy loss spectroscopy and transmission electron microscopy studies of He bubbles in Al for various He doses and temperatures result in Cexp=(24±8).10?3 eV nm3 in agreement with theory. The analysis is consistent with the assumption that dislocation loop punching is the dominant bubble growth mechanism during high-dose room temperature implantation. The application to He bubbles in Ni indicates a maximum He density of n=0.2 × 103 nm?3 for which He should be solid at room temperature. 相似文献
9.
《Surface science》1991,247(1):L201-L203
Auger electron spectroscopy has been used to monitor the adsorption of CCl4 on an As-rich GaAs(100) surface at 300 K. Intensities of the Ga (55 eV), As (34 eV), C (270 eV) and Cl (181 eV) transitions have been used to estimate surface number densities at saturation and relative C : Cl stoichiometry of the surface species. Number densities of (4.3 ± 0.2) × 1014 and (2.0 ± 0.2) × 1014 cm −2 are obtained for carbon and chlorine respectively, suggesting that coverage saturates near one theoretical monolayer and that the C : Cl stoichiometry is approximately 2:1. These data are discussed in terms of a reactive adsorption mechanism. 相似文献
10.
Abstract Isothermal annealing of amorphous Si and Ge has been performed by picosecond pulsed laser irradiation of free-standing films. It is found that the laser induced nucleation rate is about 1021-5.1022 cm?3 s?1 (Si) and 1023-1025 cm?3 s?1 (Ge) near the melting point. Arrhenius plots of the nucleation rate show that nucleation is thermally activated with an activation energy of about ΔE = 1.8 ± 0.1 eV (Ge) and ΔE = 2.47 ± 0.15 eV (Si). 相似文献
11.
R. Verucchi L. Aversa G. Ciullo A. Podestà P. Milani S. Iannotta 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,26(4):509-514
The development of electronic devices based on Silicon Carbide (SiC) has been strongly limited by the difficulties in growing
high quality crystalline bulk materials and films. We have recently elaborated a new technique for the synthesis of SiC on
clean Si substrates by means of supersonic beams of C60: the electronic and structural properties of the film can be controlled by monitoring the beam parameters, i.e. flux and particles energy and aggregation state. SiC films were grown in Ultra High Vacuum on Si(111)-7×7, at substrates temperatures of 800
°
C, using two different supersonic beams of C60: He and H2 have been used as seeding gases, leading to particles energy of 5 eV and 20 eV, respectively. Surface characterisation was
done in situ by Auger and X-Ray photoelectron spectroscopy, as well as by low energy electron diffraction and ex situ by atomic force microscopy technique. SiC films exhibited good structural and electronic properties, with presence of defects
different from the typical triangular voids.
Received 20 November 2001 相似文献
12.
D. Kieven A. Grimm I. Lauermann M. Ch. Lux‐Steiner J. Palm T. Niesen R. Klenk 《固体物理学:研究快报》2012,6(7):294-296
Valence band offsets ΔEVBM at ZnSx O1–x/Cu(In,Ga)(Se,S)2 (CIGSSe) heterojunctions have been studied by photoemission spectroscopy (XPS, UPS) as a function of composition x in sputtered ZnSx O1–x films. In the composition range from ZnO to ZnS we found ΔEVBM between –(2.1 ± 0.3) eV and –(0.8 ± 0.4) eV, respectively. Considering the optical band gaps, the conduction band offsets ΔECBM range from –(0.1 ± 0.3) eV to +(1.4 ± 0.4) eV. These results suggest that sputtered ZnSx O1–x is suitable as substitution for the CdS buffer and ZnO window layers in standard chalcopyrite‐based solar cells. Current–voltage characteristics of the solar cells have been investigated as a function of the composition x. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
13.
This paper describes the results of irradiation of specimens of copper and copper containing up to 2 at % beryllium in the high-voltage electron microscope. The results of irradiation at temperatures ranging from 20–500 K are described and discussed in the light of recently proposed theories of defect nucleation. Although the results are difficult to interpret because of the many diverse factors which influence the nucleation and growth of the damage it was found that the values for the volume density of defects were in general agreement with the predictions, if the effects of the foil surfaces were taken into account. The corrected densities were used to derive values for the activation energy for motion of an interstitial in copper, Em , and the binding energy between an interstitial and a beryllium atom, Eb . The results obtained were 0.12±0.03 eV for Em and 0.29±0.07 eV for Eb . 相似文献
14.
The binding energy of the C 1s-level of clean pyrolytic graphite and amorphous carbon has been measured by means of the excitation-curve
technique. Values ofE
C 1s
B
=284.31±0.2 eV for graphite and amorphous carbon have been found. 相似文献
15.
H. Yuki J. Kasagi A. G. Lipson T. Ohtsuki T. Baba T. Noda B. F. Lyakhov N. Asami 《JETP Letters》1998,68(11):823-829
Yields of protons emitted in the D+D reaction in Pd, Au/Pd/PdO, Ti, and Au foils are measured by a d
E-E counter telescope for bombarding energies between 2.5 and 10 keV. The experimental yields are compared with those predicted
from a parametrization of the cross section and stopping power at higher energies. It is found that for Ti and Au target the
enhancement of the D(d,p)T reaction is similar to that observed with a deuterium gas target (several tens of eV). The dependence of the yields on the
bombarding energy corresponds well to the screening potential parameters U
s=250±15 eV for Pd and 601 ±23 eV for Au/Pd/PdO. Possible models of the enhancement obtained are discussed.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 11, 785–790 (10 December 1998)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
16.
《Journal of Electron Spectroscopy and Related Phenomena》1988,46(2):419-425
Both Photoemission Yield Spectroscopy (PYS) and Auger Electron Spectroscopy (AES) have been used in the study of the electronic properties of the clean GaAs(100) surface prepared by IBA procedure and subsequently exposed to oxygen. For the clean GaAs(100)c(8 × 2) surface, the values of the work function and the absolute band bending were 4.20 ± 0.02 eV and −0.23 ± 0.06 eV, respectively, which confirms the pinning of the Fermi level EF, and two filled electronic surface state bands localized in the band gap below the Fermi level were observed. After exposition of this surface to 103 L of oxygen, the electronic surface state band localized just below the Fermi level EF disappeared, and the work function and the absolute band bending increased by only 0.12eV, whereas for the higher oxygen exposures of 104L and 105L, only small increases in the values of the work function and the absolute bending by 0.04 eV and 0.03 eV, respectively, were observed. 相似文献
17.
Emission from fullerene molecules excited by means of electron impact in crossed beams under conditions of single collisions
between electrons and C60 molecules in a kinetic energy range E
e
from 25 to 100 eV was studied experimentally. Emission spectra in a wavelength range from 300 to 800 nm; the emission excitation
functions and the temperature of emitting molecules as a function of E
e
were measured with a resolution of 1.6–3.2 nm. The contribution to emission from ionized C
60
+*
molecules has been determined and data on the emissivity of the C
60
+*
ion have been obtained. It has been shown that the emission spectra can be well approximated with the spectral distribution
of thermal emission from a black body (Planck’s formula), taking into account the lowering of emissivity for a small particle.
The emission can be observed starting with electron energy of about 27 eV; the emission excitation function is of a nonresonant
form, peaking at an energy of E
e
≈70 eV. As E
e
is increased, the temperature of emitting particles rises and reaches its maximum value of 3100–3200 K at E
e
≈47 eV. 相似文献
18.
The anisotropy of the optical properties of a single crystal of the hexagonal manganite HoMnO3 has been investigated by spectroscopic ellipsometry in the spectral range 0.6–5.0 eV. It has been demonstrated that the optical
absorption edge for the polarization E ⊥ c is determined by the intense narrow transition O(2p) → Mn(3d) centered at 1.5 eV, whereas this transition for the polarization E ‖ c is strongly suppressed and shifted toward higher energies by 0.2 eV. It has been revealed that, at the temperature T = 293 K, the spectra for both polarizations E ‖ c and E ⊥ c exhibit a broad absorption band centered at ∼2.4 eV, which was earlier observed in nonlinear spectra during optical second
harmonic generation. 相似文献
19.
O. Dragoun V. Brabec M. Ryšavý A. Špalek K. Freitag 《Zeitschrift für Physik A Hadrons and Nuclei》1987,326(3):279-285
Conversion electron measurements with an electrostatic spectrometer proved the existence of the 1,565±6 eV transition in201Hg. The conversion intensity ratios,N 1/N 2 =1.2±0.2,N 1/N 3=1.1±0.2,N 2/N 3=0.92±0.15,N 4/N 3=0.03± 0.02 andN 5/N 3=0.04 ±0.02 were determined. These values agree with our calculations for the M1±E2 multipolarity with theE2/M1 mixing ratioδ 2=(l.l±0.3)xl0?4 and exclude all pure multipolarities withL≦4. The total conversion coefficient for the aboveM1 +E2 mixture was evaluated to be (4.7±0.7)× 104. The reducedB(M1, 1/2→3/2) probability was derived to be (3.9 ±1.2) × 10?3 (e?/2Mc)2. The natural widths of theN-subshell conversion lines in mercury were found to beΓ(N 1)=8.3± 1.5,Γ(N 2) =5.8±1.5 and Γ(N 3) =6.5±1.0 eV. Monte Carlo calculations of electron scattering in matter yielded the conversion line shapes in qualitative agreement with the experiment. 相似文献
20.
Auger electron spectra have been recorded when oxygen is adsorbed on a Ni(111) single crystal surface. For the coverage range θ < 1, an analysis of the plot of the peak to peak height (H) of the oxygen KVV (516 eV) transition versus the total number of molecules cm2? impinging on the surface (molecular beam dosing) shows agreement with the kinetic mechanism proposed by Morgan and King [Surface Sci. 23 (1970) 259] for the adsorption of oxygen on polycrystalline nickel films. In this coverage range, no energy shifts of the nickel or oxygen Auger peaks were recorded.At coverages θ > 1 (standard dosing procedure) shifts in the valence spectra M2, 3VV (61 eV) and L3M2, 3V (782 eV) of ?2.3 eV and ?1.8eV respectively are recorded at 1.4 × 10?2 torr-sec. Up to these coverages no shift of the L3VV transition (849 eV) is observed. A chemical shift of ?2.1 eV is recorded in the L3M2, 3M2, 3 Auger transition (716 eV) at 1.4 × 10?2 torr-sec.In the coverage range θ > 1, shifts in the energy of the oxygen Auger peaks are observed. At 5.8 × 10?3 torr-sec. the KVV (516 eV) and KL1V (495.2 ± 0.3 eV) transitions show shifts of ?1.5 eV and ?(1.0 ±0.3) eV respectively. No shift up to this coverage is recorded in the KL1L1 (480.6 ± 0.3 eV) transition. 相似文献