X-ray photoelectron spectra and electronic structure of quasi-one-dimensional SbSeI crystals

Abstract

The paper presents the X-ray photoelectron spectra (XPS) of the valence band (VB) and of the principal core levels from the (110) and (001) crystal surfaces for the quasi-one-dimensional high permittivity SbSeI single crystal isostructural to ferroelectric SbSI. The XPS were measured with monochromatized Al Ka radiation in the energy range of 0-1400 eV at room temperature. The VB is located from 1.6 to 20 eV below the Fermi level. Experimental energies of the VB and core levels are compared with the results of theoretical ab initio calculations of the molecular model of the SbSeI crystal. The electronic structure of the VB is revealed. Shifts in the core-level binding energies of surface atoms relative to bulk ones, which show a dependency on surface crystallography, have been observed. The chemical shifts of the core levels (CL) in the SbSeI crystal for the Sb, I and Se states are obtained.

XPS analysis of sonochemically prepared SbSI ethanogel

“…The photoelectron spectra as a function of their kinetic energy were analyzed in the energy range 0-1400 eV by a hemispherical mirror analyzer with the energy resolution of about 0.3 eV. For calibration, the carbon C 1s peak (284.5 eV) was applied (as in [1,[16][17][18][19]). The state of this carbon is not clear and the binding energy of the C 1s signal might be slightly changed [1,17,20].…”

“…The shifts are towards higher/lower binding energies for the surface cations/anions [10]. In order to understand the splitting and the large shift of the CL binding energies several reasons were analyzed [1,9,[11][12][13][14][15][16], e.g. appearance of inequivalent positions of atoms due to domain boundaries, screening of polarization and charging effects, as well as antiparallel orientation of the chains.…”

XPS and electronic structure of ferroelectric Sn2P2S6crystals

“…5) it follows that from 4 to 2 eV there is a conduction band (CB), the right edge of which is formed by S 3p electrons. Unlike Sb 2 S 3 -type [1,2] and SbSI-type [3][4][5] crystals, the VB consists of five bands. It is dominated by Sn 5s, Sn 5p, S 3s, S 3p, P 3s, and P 3p states.…”

“…XPS enables one to study the surface valence changes, which affect the core-level shift with respect to the bulk atoms. Form and electronic structure of the VB and CL were studied both theoretically and experimentally in the quasi-onedimensional Sb 2 S 3 [1] and Bi 2 S 3 [2], SbSI [3], BiSI [4], and SbSeI [5] single crystals. XPS revealed huge crystallographic plane-dependent splitting of the corelevel binding energies in ferroelectric SbSI, and smaller core-level shifts in non-ferroelectric BiSI and SbSeI.…”

Investigation of the electronic structure of the SbSeBr cluster

“…For finding photoemission crosssections σ ,σ from Tables [12] we have used experimental X-ray photons energy 1486,6 eV (the X-ray photoemission spectra were obtained with monochromatic Al K α radiation at room temperature using spectrometer with energy resolution about 0.3 eV) [13][14][15].…”