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1.
Antifluorite type solid electrolytes, Li2+x-y-z[(NH)1-x-y-zNxClyHz] have been synthesized from Li3N, LiCl and LiCl·H2O or ]. Either of the last two compounds introduces NH2- ions into the product and is indispensable to form the antifluorite type structure. The lattice parameter decreases with increasing amount of NH2- ions in the compound, reflecting the difference of anion sizes between Cl- and NH2- ions. Activation energies of Li+ diffusive motion, derived from both conductivity and NMR measurements, increase with concentration of NH2- ions, although the values differ by a factor of ≈2 netween the both methods. 相似文献
2.
Comparison of the self-quenching rates of Nd3+(4F3/2) and Tb3+(5D3) in two stoichiometric materials LnP5O14 and LnNa(WO4)2, shows opposite behaviour (Ln=lanthanides). For Nd3+(4F3/2), LnNa(WO4)2 which has a small minimum Ln3+ -Ln3+ distance (), exhibits a stronger rate than LnP5O14 () with respectively a quadratic and a linear concentration dependence. On the contrary, for Tb3+(5D3), LnNa(WO4)2 exhibits a smaller rate than LnP5O14 with opposite concentration dependence. Showing that the coherent propagation is negligible, self-quenching is attributed essentially to cross-relaxation with fast or limited incoherent diffusion. Results clearly demonstrate that the existence of a structural isolation is only secondary to energy matching conditions. This in turn confirms the important role of the crystal field strength as exemplified by comparing NaLn(WO4)2 and KLn(WO4)2. 相似文献
3.
The high-spin level structures of 152Dy and 153Dy were studied experimentally with 154, 155Gd(α xnγ) in-beam reactions, and for 152Dy also with reactions. The experiments included measurements of singles γ-ray and conversion-electron spectra, γ-ray angular distributions and Eγ-t and Eγ-Eγ-t coincidences. A multiplicity filter set-up was used to study the feeding and decay of isomeric states in 152Dy. In 152Dy about twenty so far unknown levels were found, including two high-spin isomeric states with at excitation energies Ex ≈ 5.04 and 6.08 MeV, respectively. These states are compared with recent calculations on yrast traps. The level scheme of 153Dy contains 28 levels up to Ex = 4.1 MeV and . Band structures in both nuclei are discussed in comparison with other N = 86 and N = 87 isotones. 相似文献
4.
D. Denegri Y. Pons R. Barloutaud A. Borg C. Louedec M. Spiro K. Paler T.P. Shah S.N. Tovey B. Chaurand B. Drevillon G. Labrosse R. Lestienne R.A. Salmeron 《Nuclear Physics B》1975,91(1):54-68
We have studied the reaction K-p → K-π+π-π+π-p at 14.3 GeV/c to search for evidence of the double dissociation process . In the channel π1-π2-Δ++ (1236) there is evidence for simultaneous production of low-mass enhancements in the and Δ++(1236)π2- subsystems which correspond to the and decay modes. In this particular final state the double fragmentation system is produced with a cross section of the order of a few microbarns. Our data are consistent with the factorizable pomeron exchange model of double diffractive dissociation. 相似文献
5.
Optical absorption spectra of Ni2+ in (NH4)2Mg(SO4)2·6H2O and Co2+ in Na2Zn(SO4)2·4H2O single crystals have been studied at room and liquid nitrogen temperatures. From the nature and position of the observed bands, a successful interpretation could be made assuming octahedral symmetry for both the ions in the crystals. The splitting observed for band in Ni2+ and band in Co2+ at liquid nitrogen temperature have been explained as due to spin-orbit interaction. The extra band observed at 16,325 cm-1 in the case of Ni2+ at low temperature has been interpreted to be the superposition of vibrational mode of SO2-4 radical on band. The observed band positions in both the crystals have been fitted with four parameters B, C, Dq and ζ. 相似文献
6.
D. Mazumdar P.A. Govindacharyulu D.N. Bose 《Journal of Physics and Chemistry of Solids》1982,43(9):933-940
A Study of electronic conductivity using the d.c. polarization technique has been carried out in α and β-AgI which shows the former is a hole and the latter an electron conductor. Activation energies of undoped and Cu-doped single crystals and polycrystalline β-AgI were found to be 0.46 eV, 0.34 eV and 0.44 eV respectively and can be related to electron trap depths. The electron transference number () for polycrystalline β-AgI was found to be 0.008 at 306 K. The activation energy for hole conduction in α-AgI was determined to be 0.97 eV in agreement with previous XPS studies.Transient measurements have also been conducted using the charge transfer technique in double cells of polycrystalline β-AgI. The carrier concentration Cθ and electron mobility μθ, have thus been estimated to be 1.8 × and 5.14 × 10?5?sec. respectively at 306 K, while the double layer capacitance was 0.496 . 相似文献
7.
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
8.
Jon T. Hougen 《Journal of Molecular Spectroscopy》1984,106(1):134-154
Rotational energy levels in vibronic ground states of 2A, 2E, and 2F electronic states of open-shell XY4 molecules, as well as rotational line intensities for allowed transitions between such states, are discussed, including the effects of spin-orbit interaction and tetrahedral splittings. Jahn-Teller effects are assumed to be small, and are only taken into account implicitly, through their contributions to various parameters in the effective Hamiltonian. Qualitative information is obtained by considering several limiting-case coupling schemes among the electron spin angular momentum S, the electron orbital angular momentum L, and the pure rotational angular momentum R. These limiting cases are similar in spirit to Hund's coupling cases in diatomic molecules, but differ sufficiently from the latter to make detailed correspondences unhelpful. Quantitative information on rotational energy levels and line intensities is obtained numerically by diagonalizing a Hamiltonian matrix set up in a basis set characterized by uncoupled moleculefixed projections of S, L, and the total angular momentum J, and symmetrized so that all basis set functions belong to a definite species in the subgroup D2d of the true point group Td. Hamiltonian matrix elements are determined by ladder operator techniques. Three sample calculated spectra, corresponding to , , and are presented. As one might expect, when the spin-orbit constant A is set equal to zero, then both qualitative and quantitative aspects of the rotational-electronic problem in open-shell XY4 molecules can be mapped easily onto discussions of the rotation-vibration problem from the CH4 literature. 相似文献
9.
In this note we determine the oscillator strengths for the dipole absorption of neutral bound excitons in direct gap semiconductors, using our previously obtained 35-term Page and Fraser type wave function, and taking into account the detailed electronic structure as well as the electron-hole exchange interaction.The envelope part of the oscillator strengths varies considerably with the electron-hole mass ratio , and is maximum for the (D0, X)- complex when σ = 0.4. For typical σ-values (σ? 0.1–0.2), . But when σ approaches zero, the overlapping of the electron and the hole envelope wave functions of the (A0,X)-complex decreases progressively so that the oscillator strength also decreases and tends to zero.In the case of zinc-blende materials (Td) and positive spin-orbit coupling at , we confirm that the line strength for transitions to or from or level of the (A0, X)-complex is equal to one quarter of the line strength to or from the level.In the case of CdS, where our computed values are only in qualitative agreement with the experimental values, we discuss the use of the phenomenological result of Rashba. 相似文献
10.
J.C.D. Brand U.D. Deshpande A.R. Hoy S.M. Jaywant 《Journal of Molecular Spectroscopy》1983,100(1):143-150
The E-B (0g+-0u+) band system of Br2 has been investigated at Doppler-limited resolution using polarization labeling spectroscopy. Merged E state data for the three naturally occurring isotopes in the range vE = 0–16, expressed in terms of the constants for 79Br2, are (in cm?1) Y0,0 = 49 777.962(54), Y1,0 = 150.834(22), Y2,0 = ?0.4182(28), Y3,0 = 6.6(11) × 10?4, Y0,1 = 4.1876(28) × 10?2, Y1,1 = ?1.607(16) × 10?4, and Y0,2 = 1.39(39) × 10?8. The bond distance is , and the diabatic dissociation energy to . 相似文献
11.
Cross sections for fine-structure mixing in potassium, induced in collisions with N2, H2, CO, and CH4, were determined by methods of atomic fluorescence spectroscopy. The experiments were carried out at a temperature of 342 K, a K density of 6 × 109 cm?3 and mtorr buffer gas pressures, and yielded the following cross sections ) and (in units of 10?6 cm2): for N2, 79 and 54; for H2, 57 and 39; for CO, 98 and 64; for CH4, 86 and 58. The values for N2 and H2 supersede those reported previously by McGillis and Krause (1968). 相似文献
12.
A millimeter-wave spectrometer having a sensitivity of 4 × 10?10 cm?1 in the 2-mm region has been constructed for observation of extremely weak millimeter-wave spectra of gases. It has been used to measure J → J, K = 0 ← 3 transitions in PH3 and J → J, K = 0 ← 3 as well as K = ±1 ← ±4 transitions in PD3. The B0 and C0 spectral constants (in MHz) are: for PH3, B0 = 133 480.15 ± 0.12 and C0 = 117 488.85 ± 0.16; for PD3, B0 = 69 471.10 ± 0.03 and C0 = 58 974.37 ± 0.05. The effective ground-state values obtained for the bond angle and bond length are: for PH3, and ; for PD3, and . The corresponding zero-point-average values were calculated to be: for PH3, and ; for PD3, and . For both species, the equilibrium values are and . 相似文献
13.
A. Possoz Ph. Deschepper L. Grenacs P. Lebrun J. Lehmann L. Palffy A. De Moura Gonçalves C. Samour V.L. Telegdi 《Physics letters. [Part B]》1977,70(2):265-268
The helicity, h?, of μ? in π-decay has been determined as positive (h??+0.90) from the average polarization, Pav≡〈JB·sμ〉, of 12B produced in the reaction. We obtain also dynamical information on μ-capture: (i) the weak magnetism form factor, μ=4.5±1.1, and (ii) the sum of the induced pseudoscalar (gp) and the 2nd class induced tensor (gT) couplings versus gA, (. The latter result, adopting the “canonical” value of , leads to which is compatible with zero and in strong contradiction with the value ?—6 recently advocated by Kubodera, Delorme and Rho. 相似文献
14.
Calculations of vibrational and rotational level spacings of homonuclear inert gas diatomic molecules by numerical integration of the radial Schrödinger equation are presented. The potentials which were used for the ground states of Ar2, Kr2, and Xe2 were obtained from accurate fits to the molecular beam scattering data. From the calculated and Bv's, the following spectroscopic constants (in cm?1) were fitted: for Ar2ωe = 31.92, ωexe = 3.31, ωeye = 0.11, Be = 0.060, αe = 0.004; for , , , , ; for , , , , . 相似文献
15.
Ultrasonic wave velocities have been measured in SnTe single crystals with hole concentrations of 1.0 and 4.5 × 1020/cm3. The shear elastic stiffness constant C44 is sensitive to the hole concentration but is not, a result which is consistent with the valence band pockets being sited at the L points. The non-ellipsoidal, non-parabolic multivalley band model has been used to calculate the hole contribution to the elastic constants. The calculated difference between the shear constant C44 (2.78 × 1010 dyne cm-2) for the two crystals is in agreement with that measured experimentally (2.67 × 1010 dyne cm-2). The shear deformation potential constant Eu for the SnTe valence band is 7.8 eV at 293°K. 相似文献
16.
The emission spectrum of the He2 molecule has been rephotographed in the ~4000–~5700 Å region and the , , and transitions analyzed. The 4dδj3Δu, 4dπj3Πu, and states have been characterized through v = 2 and the 4dδJ1Δu, 4dπJ1Πu, , and states for v = 0. The term levels for these perturbed and l-uncoupled states have been confirmed (a) by analyses of bands with common levels from Δv = 0, ±1 sequences and (b) by analyses of the transitions between the above states from 4d and 4s and the and states associated with 3pσ. Molecular constants are reported which have been partially corrected for the effects of l-uncoupling and the homogeneous perturbations between the state pairs J, H and j, h. 相似文献
17.
Laser-induced fluorescence excitation has been used to measure Stark splittings of selected lines in the and band systems of H2CS in electric fields up to 13 kV/cm. The derived excited state a-axis dipole moments are 0.820 ± 0.007 D for the 41 level of the 1A2 state; 0.838 ± 0.008 D for the zeroth vibrational level of 1A2; and 0.534 ± 0.015 D for the zeroth vibrational level of the 3A2 state. These results are compared with the corresponding values of H2CO, and interpreted in terms of the changing localization of the π and orbitals accompanying electronic excitation. 相似文献
18.
Victor Elias 《Physics letters. [Part B]》1977,68(4):335-338
The Callan-Gross relation is shown to be consistent with MIT-SLAC data for for x ? 0.33 in deep inelastic eN scattering, despite the fact that these data are taken in the large Q2 region where F1 and F2 individually exhibit scaling violation. Comparison is made with asymptotic freedom predictions, and color excitation is proposed to explain large values of at small x. 相似文献
19.
James J. Schwab James G. Anderson 《Journal of Quantitative Spectroscopy & Radiative Transfer》1982,27(4):445-457
Experimental oscillator strengths are reported in absorption for the 2Dj-2Pj transitions of atomic chlorine using chemical titration for the quantitative production of Cl atoms. The closely spaced 2 doublet at 118.9 nm was resolved in emission using a 6.65 m normal incidence vacuum spectrometer. Multiplet emission ratios are combined with line absorption measurements to obtain the following absolute oscillator strengths: 2 (118.875 nm), 0.0050 ± 0.0010; 2 (118.877 nm), 0.068 ± 0.007; 2 (120.135 nm), 0.102 ± 0.010. 相似文献