Crystal structure of ScNiSi3

The crystal structure of the compound ScNiSi3 has been determined. The compound belongs to a new type: space group Amm 2; a=3.815+-0.003, b=3.825+-0.003, c=20.62+-0.01 A; N=20. The atom parameters have been determined by the least square method. The structure refers to a trigonal-prismatic class; coordination number of Sc atoms is 20, of Ni atoms 9, of Si atoms 9 and 7