10.48788/DVUA/JSPAOFTkach, ViraViraTkach0000-0002-2403-8607Frantsevich Institute for Problems of Materials Science of NAS of UkraineO.Y. Khyzhun0000-0001-6727-643XFrantsevich Institute for Problems of Materials Science of NAS of UkraineN.M. Denysіuk0000-0002-0492-1945Frantsevich Institute for Problems of Materials Science of NAS of UkraineLuzhnyi Ivan VasyliovychIvanyi Ivan Vasyliovych0000-0003-3809-7517Frantsevich Institute for Problems of Materials Science of NAS of UkraineDataverseUA2026ChemistryEngineeringPhysicsX-ray photoelectron spectroscopy (XPS)SemiconductorsElectronic structureCs2HgI4Ternary halide semiconductorCore-level photoelectron spectraValence band density of statesIon sputtering effectCondensed matter physicsSurface scienceSemiconductorTkach, ViraViraTkachFrantsevich Institute for Problems of Materials Science of NAS of UkraineFrantsevych Institute for Problems of Materials Science of NAS of UkraineNational Academy of Sciences of UkraineUHV ANALYSIS SYSTEM Centre, Department No. 47 of Surface Spectroscopy of Novel Materials, Frantsevich Institute for Problems of Materials Science of NAS of UkraineDataverseUANational Academy of Sciences of Ukraine2026-08-262014-11-202026-08-212026-08-242014-09-01/2014-11-20XPS experiment dataset10.1016/j.optmat.2015.01.026184783312379738807547170637095917642281292677075472953738681962586844881991000610652106871550415141769843869419510770516515686310676482202378286569243774539113674127151324798454379597117819299application/octet-streamimage/pngtext/plaintext/plainimage/pngtext/plaintext/plainimage/pngtext/plaintext/plainimage/pngtext/plaintext/plainimage/pngtext/plaintext/plainimage/pngtext/plaintext/plainimage/jpegtext/plaintext/plainimage/pngtext/plaintext/plainimage/jpegtext/plaintext/plainimage/jpegtext/plaintext/plainimage/jpegtext/plaintext/plainimage/pngtext/plaintext/plaintext/plaintext/markdownapplication/jsontext/plainapplication/json1.0CC BY 4.0Experimental X-ray photoelectron spectroscopy (XPS) dataset collected for a Cs2HgI4 single crystal synthesized via the vertical Bridgman–Stockbarger method. The dataset encompasses wide-range survey energy scans, high-resolution core-level regions (Cs 3d, Hg 4f, and I 3d), as well as low-binding-energy valence-band spectra. Measurements were conducted both on the pristine surface (cleaved in ultra-high vacuum) and following surface bombardment with low-energy Ar+ ions. The deposited files include digitized numerical spectral curves and high-quality vector plots suitable for analyzing chemical states, stoichiometry, and electronic density of states.Primary experimental XPS spectra (survey, Cs 3d, Hg 4f, I 3d core levels, and valence band) recorded for pristine and ion-etched Cs2HgI4 single crystal surfaces using a SPECS UHV system equipped with a PHOIBOS 150 analyzer., 9.0Material: Cs2HgI4 single crystal; Crystal-growth method: vertical Bridgman–Stockbarger technique; Surface condition: pristine (cleaved in UHV) and Ar+-ion irradiated; Deposited spectral regions: survey, Cs 3d, Hg 4f, I 3d, and valence band. System: SPECS UHV-Analysis-System (Germany); Electron energy analyzer: PHOIBOS 150 hemispherical analyzer; Excitation source: Mg K-alpha radiation (photon energy: 1253.6 eV); X-ray source power: 100 W (anode voltage: 10 kV, emission current: 10 mA); Analyzer pass energy: 30 eV; Analysis chamber pressure: approximately 4 × 10^-10 mbar; Binding-energy range: 1000 to -10 eV; Energy step: 0.1 eV; Dwell time: 0.1 s; Analyzer take-off angle: 90° relative to the sample surface (normal emission). The spectrometer energy scale was calibrated using the Au 4f7/2 and Cu 2p3/2 lines of pure gold and copper reference samples at binding energies of 84.00 ± 0.05 eV and 932.66 ± 0.05 eV, respectively. Charging-related energy shifts were corrected using the C 1s line of adventitious hydrocarbon contamination set at 284.8 eV. Samples were mounted on a molybdenum sample holder.Kyiv, UkraineNational Academy of Sciences of Ukraine