Polarized X-ray absorption and double refraction in vanadyl bisacetylacetonate

Abstract

J. HAUCK 237 smaller interaction. For alloys with small M content such as A 5 M the interaction seems to be too small for a formation of ordered alloys with cubic close packing because of the entropy at elevated temperatures, where A and M are mobile. (1969a). Z. Naturforsch. Teil B, 24, 251. (1969b). Z. Naturforsch. Teil B, 24, 455--456. (1969c). Z. Naturforsch. Teil B, 24, 1064Teil B, 24, -1066Teil B, 24, . ( 1970a. Z. Naturforsch. Teil B, 25, 226. (1970b). Z. Naturforsch. Teil B, 25, 109-110. (1970c). Z. Naturforsch. Teil B, 25, 749-752. (1970d). Z. Naturforsch. TeiI B, 25, 468-471. (1973). Z. Naturforsch. Teil B, 28, 215-216. (1974). J. Inorg. Nucl. Chem. 36, 2291-2298. HAUCK, J. (1976a. Z. Naturforsch. TeilB, 31, 1179-1182. HAUCK, J. (1976b structure is polarized as a result of the symmetries of molecular orbitals in this strongly anisotropic molecule. The extended X-ray absorption fine structure is polarized because of the difference in distance to the axial and equatorial oxygen neighbors. In this wavelength region, the anomalous-scattering terms and © 1980 International Union of Crystallography 238 DOUBLE REFRACTION IN VANADYL BISACETYLACETONATE the index of refraction vary with the direction of polarization. Some of the consequences and possible applications of these properties are discussed.

Chirality-induced `forbidden' reflections in X-ray resonant scattering

“…There is quite a close similarity between this effect and the anisotropy-induced re¯ections which were predicted by Templeton & Templeton (1980), theoretically developed by Dmitrienko (1983Dmitrienko ( , 1984, and experimentally observed for the ®rst time by Templeton & Templeton (1985) for the dipole± dipole transition in NaBrO 3 . They are usually called forbidden re¯ections' or ATS (anisotropy of the tensor of the susceptibility) re¯ections, because in the absence of the anisotropy they are strictly forbidden by the glide-plane and/ or screw-axis selection rules.…”

Resonant x-ray diffraction of the magnetoresistant perovskitePr0.6Ca0.4MnOGrenier1, Hill2, Gibbs3 et al. 2004Phys. Rev. B1025711View full textAdd to dashboardCite

“…Thus, this scattering at (010) is distinct from that of the pre-transitional fluctuations just above T COO observed in the σ − σ ′ channel, which exhibit temperature-dependent shortrange order [14]. Rather, this scattering represents the average long-ranged ordered component of the high-temperature structure (Templeton scattering [31]). …”

Resonant X-ray diffraction: `forbidden' Bragg reflections induced by thermal vibrations and point defects

“…These ATS (anisotropy of the tensor of susceptibility) re¯ec-tions occur even in non-magnetic crystals because the outer shells are strongly affected by the local environment and therefore the atomic scattering amplitude becomes anisotropic (Templeton & Templeton, 1980;Dmitrienko, 1983Dmitrienko, , 1984. The anisotropy violates the extinction rules tabulated for glide planes and/or screw axes.…”