A Novel Boron-Rich Scandium Borocarbide; Sc4.5−xB57−y+zC3.5−z(x=0.27, y=1.1, z=0.2)

摘要: Abstract A novel ternary boron-rich scandium borocarbide Sc 4.5− x B 57− y + z C 3.5− ( =0.27, =1.1, =0.2) was found. Single crystals were obtained by the floating zone method adding a small amount of Si. Single-crystal structure analysis revealed that compound has an orthorhombic with lattice constants =1.73040(6), b =1.60738(6) and c =1.44829(6) nm space group Pbam (No. 55). The crystal composition ScB 13.3 0.78 Si 0.008 calculated from agreed measured 12.9 0.72 0.004 . is new type borides there are six structurally independent 12 icosahedra I1—I6, one 8 /B 9 polyhedron nine bridging sites all which interconnect each other to form three-dimensional boron framework. main structural feature framework can be understood as layer where two kinds icosahedron network L1 L2 stack along -axis. There seven in open spaces between layers.