Application of the relativistic DV-X molecular orbital method to -uranium alloys with transition metals

相金属ウランと遷移金属合金の相対論DV-X分子軌道法による解析

栗原 正義*; 平田 勝 ; 尾上 順*; 中松 博英*

Kurihara, Masayoshi*; Hirata, Masaru; Onoe, Jun*; Nakamatsu, Hirohide*

相ウラン金属と4d, 5d遷移金属で構成される合金の電子状態を相対論DV-X法により解析した。ウランの5f, 6d軌道と遷移金属のd軌道との相互作用を解析して、ウラン金属中での各遷移金属の安定性を評価した。

The alloying behavior of 4d and 5d transition metals (TMs) in -phase solid uranium (U) has been investigated using the discrete-variational Dirac-Fock-Slater (DV-DFS) method. We examined the d-orbital energy (Md value) of these TMs, the orbital overlap population (OOP) between the d-orbital of these TMs and the 5f or 6d orbital of -U, and the effective charge on each atom of the -U/TM alloy, and the effect of these parameters on alloying. It was found that the maximum solid solubility of TMs into -U was exponentially proportional to both the Md and the OOP (U5f-TMd and U6d-TMd). We found a good correlation between the MSS and Md, the effective charge, or OOP.