Detail of "12046-54-7"

Reference

Potential for improvement in thermoelectric properties of hexaborides

All Rights Reserved. Potential for improvement in thermoelectric properties of hexaborides. Takeda, Masatoshi; Kurita, Yosuke (Department of Mechanical Engineering, Nagaoka University of Technology 1603-1 Kamitomioka, Nagaoka 940-2188, Japan). International Conference on Thermoelectrics, 23rd, 061/1-061/4 (English) 2004 Institute of Electrical and Electronics Engineers. CODEN: ICTNBZ. ISSN: 1094-2734. DOCUMENT TYPE: Journal; (computer optical disk) CA Section: 76 (Electric Phenomena) Thermoelec. properties and electronic structure of hexaborides were examd. to discuss the possibility of further improvement in their thermoelec. performance. Composites of 2 divalent hexaborides (CaB6 and BaB6) were prepd. and their thermoelec. properties were measured. Seebeck coeff. and elec. cond. of the composites were intermediate between those of CaB6, and BaB6. Thermal cond. 12046-08-1 and 12046-54-7 are cas registry numbers of chemicals which are used as reagents here. of the composites was lower than the both single phases of the hexaboride. As a consequence, the highest figure of merit was obtained in the composite, indicating that such a texture control using 32 hexaboride phases is effective to improve thermoelec. performance of these materials. Electronic structure calcns. were performed on the hexaborides to discuss the origin of n-type carrier and differences in carrier concn. obsd. in the divalent hexaborides. According to the calcns., there was no essential difference in the electronic structure among the divalent hexaborides (CaB6, SrB6, BaB6). And the calcns. suggested that the n-type carrier can be generated due to defect of B atoms rather than that of metal atoms. .

Electronic structure of divalent hexaborides

Electronic structure of divalent hexaborides. Massida, S.; Continenza, A.; De Pascale, T. M.; Monnier, R. (Istituto Nazionale Fisica Materia, Universita Studi Cagliari, Cagliari I-09124, Italy). Zeitschrift fuer Physik B: Condensed Matter, 102(1), 83-89 (English) 1997 Springer. CODEN: ZPCMDN. ISSN: 0722-3277. DOCUMENT TYPE: Journal CA Section: 76 (Electric Phenomena) Section cross-reference(s): 65, 75 Recent expts. suggest that divalent hexaborides like SrB6 and CaB6, traditionally considered small-gap semiconductors, can actually be semimetals. We calcd. the structural and electronic properties of SrB6, CaB6 and of ferromagnetic EuB6, using the full-potential linearized APW (FLAPW) method, within the local (spin) d. approxn. The lattice consts. and internal parameters are in very good agreement with the measured ones. Because of a small band overlap at the X point, all the materials are semimetals. The calcd. Hall coeff. for SrB6 changes sign around zero doping, and has the free-electron value for doping beyond u1.5%. The plasma frequency has a min. at zero doping. We interpret the high-temp. transport properties of SrB6 and CaB6 in terms of a thermal gap deduced from the shape of the d. of states around the Fermi energy. We also calcd. 12007-99-7 and 12046-54-7 are just another two chemicals used in this study. the imaginary part of the dielec. function for SrB6, which can be compared to recent expts. .