Abstract
The obtained experimental valence band structures of the ZrSe2 (above) and ZrS2 (below). The agreement between the obtained experimental and the calculated band structure (solid lines) in generally very good for the parallel directions of the BZ.
•The studied crystals were grown by the chemical vapor transport.•The whole series have similar band structure feature.•Experimental results are in a good agreement with calculations data.•The topmost valence binding energy depends on composition.•An emission from the conduction band minimum was observed.
The electronic structure of the ternary layered transition metal dichalcogenide compounds of ZrSxSe2−x, where 0≤x≤2, has been studied by means of high resolution angle-resolved photoemission spectroscopy (ARPES) used in conjunction with synchrotron radiation facilities. The crystals were grown by the chemical vapor transport technique using iodine as a transport agent. They are found to be degenerate extrinsic n-type semiconductors with an indirect bandgap character. The experimental valence band structure of the complete series of ZrSxSe2−x is reported along the major symmetry azimuthal directions in the Brillouin zone parallel to the layers. The results show that the binding energies of the topmost valence band shift almost linearly with the composition parameter x. Further, an emission from the conduction band minimum observed just below the Fermi edge enabled us to estimate the energy gap values. The electronic structure deduced from the photoemission measurements are discussed and compared to band structure calculations.