Electronic structure of the pyrochlore metals Cd2Os2O7 and Cd2Re2O7 -: art. no. 155109
Electronic structure of the pyrochlore metals Cd2Os2O7 and Cd2Re2O7 -: art. no. 155109
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DOI：
10.1103/physrevb.65.155109
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发表时间：
2002-04-15
影响因子：
3.7
通讯作者：
Sofo, JO
中科院分区：
文献类型：
--
作者：
Singh, DJ;Blaha, P;Sofo, JO
报告了烧绿石 Cd2Os2O7 和 Cd2Re2O7 的局部自旋密度近似和广义梯度近似内的第一原理密度泛函计算。发现过渡金属 t(2g) 流形在能量上与 O 2p 能带以及更高位置的 e(g) 和 Cd 衍生能带很好地分离。发现费米能 E-F 附近的 t(2g) 流形中的活性电子结构受到自旋轨道相互作用的显着改变，我们将其包括在内。两种材料均显示出半金属能带结构，其中 E-F 位于赝能隙中。 Cd2Os2O7 靠近 E-F 的能带结构主要是重空穴和电子能带，尽管在 E-F 处电子部分较轻。 Cd2Re2O7 具有重空穴能带，但具有中等质量的电子态。根据这些化合物的测量的传输和热力学性质以及这两种材料的非常不同的基态来讨论结果。
First-principles density-functional calculations within the local spin-density approximation and the generalized gradient approximation are reported for pyrochlore Cd2Os2O7 and Cd2Re2O7. The transition-metal t(2g) manifolds are found to be well separated in energy from the O 2p bands and from the higher-lying e(g) and Cd derived bands. The active electronic structure in the t(2g) manifold near the Fermi energy E-F is found to be significantly modified by spin-orbit interactions, which we include. Both materials show semimetallic band structures, in which the E-F lies in an pseudogap. The band structure of Cd2Os2O7 near E-F is dominated by very heavy-hole and electron bands, though at E-F the electron sections are lighter. Cd2Re2O7 has heavy-hole bands but moderate mass electron states. The results are discussed in terms of measured transport and thermodynamic properties of these compounds as well as the very different ground states of these two materials.