| Autor: |
Pavan Kumar Naik S; Research Institute for Advanced Electronics and Photonics, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Central 2, Umezono, Tsukuba, Ibaraki 305-8568, Japan.; Department of Physics, Tokyo University of Science, 1 Chome-3 Kagurazaka, Shinjuku City, Tokyo 162-8601, Japan., Iwasa Y; Research Institute for Advanced Electronics and Photonics, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Central 2, Umezono, Tsukuba, Ibaraki 305-8568, Japan.; National Metrology Institute of Japan (NMIJ), National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Central 3, Umezono, Tsukuba, Ibaraki 305-8568, Japan., Kuramochi K; Research Institute for Advanced Electronics and Photonics, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Central 2, Umezono, Tsukuba, Ibaraki 305-8568, Japan.; Department of Physics, Tokyo University of Science, 1 Chome-3 Kagurazaka, Shinjuku City, Tokyo 162-8601, Japan., Ichihara Y; Department of Applied Chemistry, The University of Tokyo, 7 Chome-3-1 Hongo, Bunkyo City, Tokyo 113-8654, Japan., Kishio K; Department of Applied Chemistry, The University of Tokyo, 7 Chome-3-1 Hongo, Bunkyo City, Tokyo 113-8654, Japan., Hongo K; Research Center for Advanced Computing Infrastructure, JAIST, Asahidai 1-1, Nomi, Ishikawa 923-1292, Japan., Maezono R; School of Information Science, JAIST, Asahidai 1-1, Nomi, Ishikawa 923-1292, Japan., Nishio T; Department of Physics, Tokyo University of Science, 1 Chome-3 Kagurazaka, Shinjuku City, Tokyo 162-8601, Japan., Ogino H; Research Institute for Advanced Electronics and Photonics, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Central 2, Umezono, Tsukuba, Ibaraki 305-8568, Japan. |
| Abstrakt: |
New CrAs-based layered mixed-anion compounds Sr 2 ScCrAsO 3 (SrScO-21113) and Ba 3 Sc 2 Cr 2 As 2 O 5 (BaScO-32225) were synthesized, and their electronic structures and physical properties were investigated. The structures of these compounds comprise stacking of the anti-fluorite CrAs layer and perovskite-like SrScO or BaScO layers. The lattice constants of these compounds are relatively longer than those of the related compounds, such as BaCr 2 As 2 , owing to the insertion of a large perovskite blocking layer of SrScO/BaScO. While there are variations in the crystal structure of this system, such as 21113 and 32225, their chemical stability calculated by the first-principles calculations indicated that SrScO-21113 is energetically favorable compared to SrScO-32225. The formation energies of BaScO-32225 and BaScO-21113 are close to each other; in the experiment, while there was an indication of BaScO-21113 formation, only BaScO-32225 was formed as a single phase because of the low chemical stability of BaScO-21113. The partial density of states indicates that the majority of states are obtained from the 3 d 4 -electrons of the Cr element hybridized modestly with p electrons at the Fermi energy. The magnetic properties of these compounds were paramagnetic, and they were different from related compounds, such as BaCr 2 As 2 , probably because of their long a -axis lengths. The temperature dependences of the electrical resistivities of both samples were in good agreement with the electronic band structure calculations. The variety of structures in the series of compounds with a CrAs layer results in different physical properties, and further development of new compounds may bring novel functionalities, such as superconductivity. |
