共查询到20条相似文献,搜索用时 46 毫秒
1.
J.M. Tarascon J.V. Waszczak G.W. Hull F.J. DiSalvo L.D. Blitzer 《Solid State Communications》1983,47(12):973-979
New ternary molybdenum chalcogenides HgxMo6S8 (0 < x < 1) have been synthesized and investigated for their structural, magnetic, and superconducting behavior. These new phases prepared at low temperature by reaction of mercury with Mo6S8 (obtained from oxidation of Cu2Mo6S8 by iodine) have been characterized by x-ray diffraction, static Faraday susceptibility, and superconducting transition temperature studies. HgMo6S8 crystallizes in the rhombohedral space group , has a paramagnetic, temperature dependent susceptibility, and superconducts at 8.1K. As the mercury content decreases, a continuous decrease in Tc from 8.1K to 1.7K for x=0 (Mo6S8) is observed. 相似文献
2.
Cr has a well developed magnetic moment in a Cd host and the superconducting transition temperature, Tc, is strongly depressed. We estimate a spin, S = 1.5 leading to a depression rate - . The s-d interaction strength is estimated to 0.5–0.7 eV leading to a Kondo temperature in the milliKelvin range. 相似文献
3.
We examine the Hamiltonian , where uo, u8 belong to and Sαα, Sαβ belong to (8,8), following a purely algebraic approach due to Michel and Radicati and obtain B/A = 2√3 if ε8/ε0 = ?√2. 相似文献
4.
EPR spectra at 35 and 60 GHz of Gd3+ diluted (~1%) in powdered SnMo6S8 and PbMo6S8 are presented and interpreted. The crystal field is found to be axial, with D = b20=-760 gauss and -740 Gauss for the tin and lead compounds respectively. Values are obtained for <J(q)> and J(q = 0). Below Tc the impurity to conduction electron relaxation rate is no longer proportional to temperature but decreases more rapidly. From this temperature dependence we extract a value for of roughly 5 for both compounds. 相似文献
5.
We report on the first measurements of the critical field Bc2 and the specific heat of Nb3S4, which is a linear structured compound with a superconducting transition temperature of 3.65 K. The angular dependence of Bc2 is well described by the effective-mass model. The ratio of the critical fields parallel and perpendicular to the c-axis gives a value of 4.6. The small value of the specific heat jump at can be explained with an anisotropic gap function. 相似文献
6.
Nearest neighbour anisotropic exchange is characterized by for a bond along the x-axis. For J6 = ?J⊥ < 0 the ground configuration of the total exchange hamiltonian is a two-sublattice antiferromagnet which is an eigenstate of the problem. 相似文献
7.
C.V.K. Baba D.B. Fossan T. Faestermann F. Feilitzsch P. Kienle C. Signorini 《Physics letters. [Part B]》1973,43(6):483-486
The difference in g-factors for the 61+ and 81+ states in 210Po has been measured as . This result represents a small violation of additivity. A value of g8 = 0.909 ± 0.011, independent of g6, was also obtained. 相似文献
8.
Etude des proprietes thermodynamiques d'un groupement tetranucleaire: Application au compose Na3RuO4
The exact eigenvalues spectrum of the spin hamiltonian have been calculated for a tetranuclear cluster formed by four spins 3/2 at the vertices of a lozenge. Two isotrope exchange interactions J1 and J2 are able to explain the thermodynamic properties (magnetic susceptibility, entropy, specific heat). A ground state transition from singlet to triplet state occurs when the ratio reaches the value . The magnetic susceptibility data of Na3RuO4 fit well with the theoretical values proposed for and J2/k (?22,5 K). 相似文献
9.
The cross section for the reaction has been measured at θlab = 135° over the proton energy range 93 ≦ Ep ≦ 418 keV. The results are in good agreement with the less precise but much earlier measurements of Schardt, Fowler and Lauritsen (1952). An analysis of the present data in terms of a two-level calculation including the 338 keV (1?) and 1028 keV (1?) resonances determines a zero-energy intercept for the astrophysical S-factor of S(0) = 78 ± 6 MeV · b. 相似文献
10.
Mössbauer emission spectra of a frozen aqueous solution of 57CoCl2 show contributions from the and the Zeeman levels of Fe3+ ions at T = 4.2 K in H ? 30 kG. The K-capture results in a non-equilibrium state of relaxation time comparable to the lifetime of the nuclear excited state (~ 10?7 s). 相似文献
11.
The emission and excitation spectra of the aromatic thioketone xanthione have been measured in Shpolskii matrices at 15 K. Under these conditions a sharp and rich vibrational structure is observed in the lowest triplet and the first and second excited singlet states. The phosphorescence excitation spectrum places the origin of the T1 ← S0 transition at 15 143 cm?1, while that of the absorption is tentatively assigned to the band at 16 093 cm?1. The phosphorescence spectrum, which shows only a weak CS stretch vibrational band, is dominated by ring vibrations. In accordance with the previous analysis of ODMR measurements, it is suggested that T1 and T2 states are energetically very close, thereby resulting in a lowest triplet state of heavily mixed n, , character. No mirror-image relationship is found between the relatively strong S2 → S0 fluorescence and the excitation spectrum of the transition. The latter is dominated by a long, pronounced 336-cm?1 progression. 相似文献
12.
Neutron pick-up cross sections and vector analyzing powers have been measured for the reaction 55Mn(, t)54Mn at 17 MeV. The mixture of to transfer to the low-lying ln = 1 states has been found. Evidence of the hole nature of several strong ln = 3 states above 1 MeV has been obtained. 相似文献
13.
E. Molva J.P. Chamonal G. Milchberg K. Saminadayar B. Pajot G. Neu 《Solid State Communications》1982,44(3):351-355
We report on resonantly excited luminescence (REL) at 1.8 K and infrared absorption (IRA) between 6–12 K of CdTe doped with Ag and Cu impurities. The luminescence was excited with a tunable dye laser. Two hole transitions up to state have been observed, the bound exciton lines have been identified. states have been observed in IRA measurements. The binding energies as deduced from REL experiments are 107.5 meV for Ag and 146 meV for Cu. The fitted values of the valence band parameters are Ro = 27 ± 3 meV μ = 0.73 ± 0.03 and δ = 0.12 ± 0.01. 相似文献
14.
The infrared absorption spectrum of a single crystal of MoSe2 is reported. A damped oscillator fit to the fundamental band gives the transverse optic frequency, at 300° K and at 77° K. The static and high frequency dielectric constants have been determined as Ks = 16.81 and K∞ = 10.24 respectively. An absorption band appears in the i.r. spectrum at 482 cm-1, and has been attributed to the oxygen impurity in the crystal. 相似文献
15.
The reaction of carbon monoxide with oxygen chemisorbcd on polycrystalline platinum has been studied using Auger spectroscopy. Two types of chemisorbed oxygen are distinguished on the basis of Auger electron chemical shifts and reactivity towards carbon monoxide. When the substrate is below 800 K, a single very reactive type of chemisorbed oxygen is formed. Above 800 K a new species begins to form which is characterized by an Auger chemical shift of about 6 eV and by low reactivity. The decay of the oxygen Auger signal using several fixed pressures of carbon monoxide was measured. The reaction is first order in carbon monoxide pressure but no clear decision can be made about the order with respect to oxygen coverage. With the reaction operating at steady-state, the oxygen coverage was measured as a function of CO pressure. In the region 363–600 K, the steady state oxygen coverage began to decline measurably when reached 0.1. When pCO>pO2the oxygen coverage became immeasurably small. A simple model is used to relate these phenomena to observed carbon dioxide production rates. 相似文献
16.
Marek Danielewski Jaeosław Da̧bek Stanisł;aw Mrowec Grażyna Siemińska 《Solid State Ionics》1985,17(4):331-335
Using the re-equilibration kinetic method the chemical diffusion coefficient in nonstoichiometric chromium sesquisulfide, Cr2+yS3, has been determined as a function of temperature (1073–1373 K) and sulphur vapour pressure (10?104 Pa). It has been found that this coefficient is independent of sulphur pressure and can be described by the following empirical equation: . It has been shown that the mobility of the point defects inCr2+yS3 is independent of their concentration and that the self-diffusion coefficient of chromium in this sulfide has the following function of temperature and sulphur pressure: . (cm2s?1). 相似文献
17.
The microwave spectrum of MnO3F has been remeasured and several corrections and new results have been obtained: B0 = 4129.141 MHz, DJ = 1.12 kHz, DJK = 1.87 kHz; , , , |q5| = 16.005, and |q6| = 8.456 MHz. 相似文献
18.
J. Kwiatkowski 《Reports on Mathematical Physics》1973,4(3):203-210
The purpose of this paper is to prove the following theorem.Theorem. Given a countable subset Λ on the circle K and an integer-valued function n(λ) on Λ, there exists a dynamical system with discrete spectrum (X,,μ,T) such that Λ is the set of all eigenvalues of T and n(λ) is the multiplicity function of T if and only if there exist two systems of subgroups {Gi}i∈N and of the circle such that Λ = G ∪ S and where . 相似文献
19.
O.V. Nielsen T. Johansson L.M. Holmes G.J. Cock L.W. Roeland A.A. Ballman 《Journal of magnetism and magnetic materials》1976,1(4):320-325
The magnetic properties of MnNb2O6 single crystals have been studied in the temperature range 1.6–300 K (TN = 4.4 K), in fields up to 220 kOe. The high field saturation at low temperature, as well as the paramagnetic susceptibility at high temperature, agree well with a state for Mn2+ ions. From 1.6 to 3.8 K a spin flop is induced by fields ranging from 17 to 21 kOe, applied in the direction of the a-axis. Elements of the magnetic susceptibility tensors up to rank 12, measured below the spin flop field, are in accordance with a magnetic anisotropy originating mainly from magnetic dipolar interactions. 相似文献
20.
Superconductivity and crystal structure data are reported for a series of ternary CuxMo3S4 samples with 0 ≤ x ≤ 1 which were prepared by anodic oxidation of Cu1.0Mo3S4. A phase with the composition Cu0.5Mo3S4 was found to have rhombohedral lattice parameters and αR = 93.74(4) ° and a superconducting critical temperature Tc = 5.8 K. The dependence of Tc on pressure for Cu0.5Mo3S4 has been measured between 0 and 19 kbar. 相似文献