부산대학교 도서관

In the reported synthesis of several rare earth dodecaborides from metal oxides and boron, TbB/sub 12/ and YbB/sub 12/ were among the borides which could not be prepared. Efforts were made to synthesize YbB/sub 12/ TbB/sub 12/ and GdB/ sub 12/ using the pure metals which were arc melted with boron under argon. YbB/ sub 12/ and TbB/sub 12/were obtained as facecentered cubic phases with respective lattice constants of 7.469 and 7.504 A, while only GdB/sub 6/ was obtained from Gd. Crystallographic data for the new dodecaborides are tabulated along with these for the other rare earth dodecaborides. (D.L.C.)