Spherical cluster method for ground state determination of site-disordered materials: Application to AgxBiyIx+3y

Tale of Two Sites: Band-Gap Tuning in AgBiI4 through Site-Selective Alloying

“…The mapping in the SEM images indicated that the elements had a uniform composition within the deposited films (Figure S1 in the Supporting Information). As stated, the semiconductor and its alloys are known to possess either a CdCl 2 -type rhombohedral or a cubic defect spinel structure having an R 3̅ m or Fd 3̅ m space group symmetry. , Although prior analysis based on density functional theory (DFT) calculations shows that the structure is best described to be CdCl 2 -type, a very recent DFT study utilizing the spherical cluster method inferred that the spinel structure has a lower ground-state energy . It may, however, be stated that the structure has little or no effect on the electronic properties of the material …”

“…18,28 Although prior analysis based on density functional theory (DFT) calculations shows that the structure is best described to be CdCl 2 -type, 11 a very recent DFT study utilizing the spherical cluster method inferred that the spinel structure has a lower ground-state energy. 29 It may, however, be stated that the structure has little or no effect on the electronic properties of the material. 28 In the Ag 1−x Cu x BiI 4 alloys, the major peak in the patterns was found to shift slightly in a nonmonotonic fashion.…”