電場勾配の異方的な結晶場中では nuclear quadrupole frequency (γQ)の温度依存性は
γQ = γQ_T=0 (1-αT^3/2)
となるそうです。
関係論文
理論
P. Jena, Phys. Rev. Lett. 36, 418 (1976)
実験
Temperature Dependence of the Electric Field Gradient in a Quasi-Two-Dimensional Metal: NbSe2
D. R. Torgeson and F. Borsa, Phys. Rev. Lett. 37, 956–959 (1976)
第一原理計算 ただし hcp Cd
D. Torumba1, K. Parlinski2, M. Rots1, and S. Cottenier1
Phys. Rev. B 74, 144304 (2006) [6 pages]
Temperature dependence of the electric-field gradient in hcp-Cd from first principles
On the temperature dependence and magnitude of the electric field gradient in noncubic metals
K W Lodge 1979 J. Phys. F: Met. Phys. 9 2035 doi:10.1088/0305-4608/9/10/013
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Phys. Rev. 128, 2207–2218 (1962)
Mössbauer Effect in Metallic Iron
R. S. Preston, S. S. Hanna, and J. Heberle
Argonne National Laboratory, Argonne, Illinois
See Also: Erratum
Received 26 July 1962; published in the issue dated December 1962
The Mössbauer effect in metallic iron has been studied from 4 to 1300°K, with particular emphasis on the region near the Curie temperature at 1043°K.
Measurements of the internal field Hn at the nucleus agree with nuclear magnetic resonance measurements and follow closely, but not exactly, the saturation magnetization curve of iron. No internal field is observed above the Curie temperature. At room temperature Hn=330±3 kOe. The ratio of magnetic moments of the two lowest levels of Fe57 is μ1/μ0=-1.715±0.004.
The observed temperature shift in the energy of the resonant radiation may be attributed chiefly to relativistic time dilation. In the low-temperature region the variation is nonlinear and compatible with a Debye temperature θ=400±30° K, although the data indicate that θ is not strictly independent of temperature. At high temperatures, the classical limit (1/E)∂E/∂T=-3k/2Mc2 for the relativistic shift is attained and perhaps exceeded. Disagreement with the classical limit would indicate a temperature variation in the isomer shift. At the Curie point and at the transition from α to γ iron, the discontinuities observed in the temperature shift are too great to be attributed to the relativistic shift. If attributed to the isomer shift, these discontinuities indicate that the electron density at the nucleus increases at the transitions from the ferromagnetic to the paramagnetic state and from α to γ iron.
The strength of the resonant absorption was also determined as a function of temperature. These measurements are compatible with a Debye temperature that falls from about 400 to 300°K in passing from low to high temperatures over the range studied.
Analysis of Debye-Waller—Factor and Mössbauer-Thermal-Shift Measurements. II. Thermal-Shift Data on Fe
Phys. Rev. 164, 340–344 (1967)
R. M. Housley
North American Aviation Science Center, Thousand Oaks, California
F. Hess
Natuurkundig Laboratorium, University of Groningen, Groningen, Netherlands
Received 5 June 1967; published in the issue dated December 1967
Techniques developed in a previous paper are used to subtract the second-order Doppler contribution from measured thermal shifts on pure Fe and dilute Fe in various hosts. This allows the temperature dependence of the isomer shift arising from the electron density at the nucleus to be seen more clearly than was previously possible. It is shown that this temperature dependence cannot be accounted for by thermal expansion alone. In pure Fe a contribution related to the magnetization is clearly evident, as is theoretically expected. A contribution in addition to this and the thermal-expansion contribution is present, contrary to the conclusion generally drown from previous work. The additional contribution to the isomer shift is discussed in terms of two theories which have been used to explain the temperature dependence of hyperfine coupling constants.
以下
Mossbauer studies of helimagnetic FeAs
S. K. Kulshreshtha and P. Raj (1979)
より抜粋
We would like to point out that for FeAs, the temperature dependence of qtotal
has been found to be very close to linear rather than of T 3 ’ 2 type, suggesting that
the semi-empirical expression (1) does not hold good. It is doubtful whether such
a semi-empirical approach can be extended t o intermetallic compounds exhibiting
metallic behaviour, because in many other systems the quadrupole interaction is
reported to be independent of temperature, over a wide range of temperature [see
for example Haggstrom er a / (1974, 1975) Raj and Kulshreshtha (1976)l
