The crystal structure and properties of a new member of the oxybismuth sulfide family SmO0.5F0.5BiS2 are reported here. The compounds SmO1–x F x BiS2 (x = 0.0 and 0.5) are isostructural with LaOBiS2 ...and crystallize in the CeOBiS2-type structure (P4/nmm). Sm substitution in LaO0.5F0.5BiS2 (La1–y Sm y O0.5F0.5BiS2) leads to a gradual decrease in the a-lattice constant; however, the c-lattice constant does not show such a gradual trend. Enhancement in T c is achieved upon partial substitution of La by the smaller Sm ion. A maximum T c ∼ 4.6 K was observed for composition with y = 0.8. Disobeying this trend, T c disappears unexpectedly in the composition SmO0.5F0.5BiS2 (y = 1.0). Both the undoped and F-doped (x = 0.0 and 0.5) compounds are paramagnetic, exhibiting semiconducting behavior down to 2 K.
GenURC Zimmermann, Gottfried; Jordan, J. Bern; Thakur, Parikshit ...
Proceedings of the 10th International Cross-Disciplinary Conference on Web Accessibility,
05/2013
Conference Proceeding
The Universal Remote Console (URC) framework enables pluggable user interfaces. It is suitable for applications where the "one-size-fits-all approach" fails due to a heterogeneous user group with ...diverse needs and preferences. This paper reports about research and development work aiming at extending the URC's adapt-at-design-time approach by a complementary adapt-at-runtime approach. A new component (GenURC) within the URC environment generates a personal and context-driven user interface in a two-step process. A rich grouping file is used as an intermediate user interface description, containing "flexion points" for runtime adaptations based on the use context. This will allow for the integration of the URC framework with the GPII user preference model.
We have investigated the pressure effect on the newly discovered samarium doped La1-xSmxO0.5F0.5BiS2 superconductors. More than threefold increase in Tc (10.3 K) is observed with external pressure ...(at ~1.74 GPa at a rate of 4.08 K/GPa)) for x = 0.2 composition. There is a concomitant large improvement in the quality of the superconducting transition. Beyond this pressure Tc decreases monotonously at the rate of -2.09 K/GPa. In the x = 0.8 sample, we do not observe any enhancement in Tc with application of pressure (up to 1.76 GPa). The semiconducting behavior observed in the normal state resistivity of both of the samples is significantly subdued with the application of pressure which, if interpreted invoking thermal activation process, implies that the activation energy gap of the carriers is significantly reduced with pressure. We believe these observations should generate further interest in the La1-xSmxO0.5F0.5BiS2 superconductors.
We have synthesized two new Eu-based compounds, EuSr2Bi2S4F4 and Eu2SrBi2S4F4
which are derivatives of Eu3Bi2S4F4, an intrinsic superconductor with Tc = 1.5
K. They belong to a tetragonal structure ...(SG: I4/mmm, Z = 2), similar to the
parent compound Eu3Bi2S4F4. Our structural and 151Eu M\"ossbauer spectroscopy
studies show that in EuSr2Bi2S4F4, Eu-atoms exclusively occupy the
crystallographic 2a-sites. In Eu2SrBi2S4F4, 2a-sites are fully occupied by
Eu-atoms and the other half of Eu-atoms and Sr-atoms together fully occupy
4e-sites in a statistical distribution. In both compounds Eu atoms occupying
the crystallographic 2a-sites are in a homogeneous mixed valent state ~ 2.6 -
2.7. From our magnetization studies in an applied H = 9 Tesla, we infer that
the valence of Eu-atoms in Eu2SrBi2S4F4 at the 2a-sites exhibits a shift
towards 2+. Our XPS studies corroborate the occurrence of valence fluctuations
of Eu and after Ar-ion sputtering show evidence of enhanced population of
Eu2+-states. Resistivity measurements, down to 2 K suggest a semi-metallic
nature for both compounds.
The high-spin states in odd-odd \(^{194}\)Tl nucleus have been studied by populating them using the \(^{185,187}\)Re(\(^{13}\)C, xn) reactions at 75 MeV of beam energy. \(\gamma-\gamma\) coincidence ...measurement has been performed using the INGA array with a digital data acquisition system to record the time stamped data. Definite spin-parity assignment of the levels was made from the DCO ratio and the IPDCO ratio measurements. The level scheme of \(^{194}\)Tl has been extended up to 4.1 MeV in excitation energy including 19 new gamma ray transitions. The \(\pi h_{9/2} \otimes \nu i_{13/2}\) band, in the neighboring odd-odd Tl isotopes show very similar properties in both experimental observables and calculated shapes. Two new band structures, with 6-quasiparticle configuration, have been observed for the first time in \(^{194}\)Tl. One of these bands has the characteristics of a magnetic rotational band. The cranked shell model calculations, using a deformed Woods-Saxon potential, have been performed to obtain the total Routhian surfaces in order to study the shapes of the bands and the band crossing in \(^{194}\)Tl. The semiclassical formalism has been used to describe the magnetic rotational band.
We have synthesized two new Eu-based compounds, EuSr2Bi2S4F4 and Eu2SrBi2S4F4 which are derivatives of Eu3Bi2S4F4, an intrinsic superconductor with Tc = 1.5 K. They belong to a tetragonal structure ...(SG: I4/mmm, Z = 2), similar to the parent compound Eu3Bi2S4F4. Our structural and 151Eu M\"ossbauer spectroscopy studies show that in EuSr2Bi2S4F4, Eu-atoms exclusively occupy the crystallographic 2a-sites. In Eu2SrBi2S4F4, 2a-sites are fully occupied by Eu-atoms and the other half of Eu-atoms and Sr-atoms together fully occupy 4e-sites in a statistical distribution. In both compounds Eu atoms occupying the crystallographic 2a-sites are in a homogeneous mixed valent state ~ 2.6 - 2.7. From our magnetization studies in an applied H = 9 Tesla, we infer that the valence of Eu-atoms in Eu2SrBi2S4F4 at the 2a-sites exhibits a shift towards 2+. Our XPS studies corroborate the occurrence of valence fluctuations of Eu and after Ar-ion sputtering show evidence of enhanced population of Eu2+-states. Resistivity measurements, down to 2 K suggest a semi-metallic nature for both compounds.
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