Ti5Se4:: The first step of cluster condensation with titanium selenides

A new Ti5Te4-type Compound, Ti5Se4, has been identified and its structure is refined against x-ray powder diffraction data with the Rietveld method. It has a body-centered tetragonal unit cell with lattice parameters a = 9.6728(1) Angstrom, c = 3.5083(1) Angstrom, space group I4/m. This compound is the first titanium selenide which consists of separated M5X4 (M = metal, X = metalloid) chains. The effect of atomic radii on the formation of the Ti5Te4-type structure is discussed.