ATOMIC DEFECTS ON THE SURFACE OF QUASI TWO-DIMENSIONAL LAYERED TITANIUM DICHALCOGENIDES: STM EXPERIMENT AND QUANTUM CHEMICAL SIMULATION
A. S. Razinkin, A. N. Enyashin, T. V. Kuznetsova, A. N. Titov, M. V. Kuznetsov, A. L. Ivanovskii
Keywords: titanium dichalcogenides, atomic surface defects, STM microscopy, quantum chemical simulation
Pages: 765-771
Abstract
The atomic surface structure of layered dichalcogenide 1T-TiSe2 is studied by scanning tunneling microscopy (STM) at room temperature. In STM images, the ordered structures in the form of 6×6×6 triangles of Se atoms extending for 0.3±0.20 Å above the crystal surface are observed. The effect of a series of different atomic structural defects on the surface topology of titanium disulphide is modeled on the example of isostructural and isoelectronic 1T-TiS2 system using the DFTB method. It is determined that a good agreement with the STM experiment is showed by the model of local 1T-TiS2 packing defects, where the coordination of titanium atoms changes from the octahedral to the prismatic one. For these systems, the calculation results of the electronic structure and defect formation energy are also presented.
|
