Search results for "Electric field gradient"
showing 5 items of 15 documents
The Electric Field Gradient and the Quadrupole Interaction
1984
The Mossbauer effect has become a popular method in analytical chemistry. In contrast to other techniques such as x-ray spectroscopy, NMR, EPR, and MCD where highly sophisticated evaluation procedures are applied to obtain reliable information on the chemical compound, the Mossbauer effect is generally used on a low level concerning the evaluation of quadrupole split spectra. This procedure on a low level is favored by the structure of the spectra especially the simple doublet of the 3/2 → 1/2 nuclear transitions in paramagnetic and diamagnetic compounds. The separation of the two absorption lines, the quadrupole splitting ΔE Q and the center of the two lines, the isomer shift, are easily d…
Nuclear Resonance Scattering Using Synchrotron Radiation (Mössbauer Spectroscopy in the Time Domain)
2010
Conventional Mossbauer spectroscopy (MS) can be considered as “spectroscopy in the energy domain.” It has been widely used since its discovery in 1958 [1]. Nuclear resonant forward scattering (NFS) of synchrotron radiation has been successfully employed as a time-differential technique since 1991 [2]. Another related technique, nuclear inelastic scattering (NIS) of synchrotron radiation [3], can be regarded as an extension of conventional, energy-resolved MS (in the range 10−9 to 10−7 eV) to energies on the order of molecular vibrations (in the range 10−3 to 10−1 eV). So far only a few “Mossbauer” stations for NFS and NIS measurements have become available in synchrotron laboratories, i.e.,…
Ferromagnetic ordering in GdPdCd
2010
Abstract GdPdCd was obtained in pure form via reaction of the elements in a sealed tantalum tube in a high-frequency furnace. The structure was investigated by X-ray diffraction on both powders and single crystals: ZrNiAl type, P 6 2m , a=758.2(1), c=391.78(7) pm, wR2=0.0410 for 358 F2 values and 14 variables. Striking structural motifs of GdPdCd are two types of palladium-centered tricapped trigonal prisms [Pd1Cd3Gd6] and [Pd2Cd6Gd3]. Together the palladium and cadmium atoms build a three-dimensional network in which the gadolinium atoms fill distorted pentagonal channels. Susceptibility measurements reveal Curie–Weiss behaviour with an effective magnetic moment of 8.2(1) μB/Gd. GdPdCd ord…
Orientation of the electric field gradient and ellipticity of the magnetic cycloid in multiferroic BiFeO3
2016
This work was supported by Uniwersytet Pedagogiczny.
Resonance in Interacting Induced-Dipole Polarizing Force Fields: Application to Force-Field Derivatives
2009
The Silberstein model of the molecular polarizability of diatomic molecules, generalized by Applequist et al. for polyatomic molecules, is analyzed. The atoms are regarded as isotropically polarizable points located at their nuclei, interacting via the fields of their induced dipoles. The use of additive values for atom polarizabilities gives poor results, in some cases leading to artificial predictions of absorption bands. The molecular polarizability of methane and its derivative are computed. The agreement with experimental mean molecular polarizabilities is within 1–5%. A hypothesis is indispensable for a suitable representation of polarizability derivative.