Insight into enhanced thermoluminescence property of (Mg, Cu, Ag)-Doped LiF:A DFT study

Modulating the optical and electrical properties of oxygen vacancy-enriched La2Ce2O7:Sm3+ pyrochlore: role of dopant local structure and concentration

“…We checked the feasibility for the formation of oxygen vacancy defects by calculating the defect formation energy using the relationship below. 47,48 To find out the preferred lattice site for Sm-doping into La 2 Ce 2 O 7 , the defect formation energies of different configurations were computed. We also investigated the thermodynamic feasibility of the formation of a Sm Ce –V O complex.where, E defect and E perfect represent the energy of La 2 Ce 2 O 7 with defects and defect-free, respectively, calculated with the same supercell size; μ x indicates the chemical potential of the element X; and n x is the number of elements added ( q = −1) or replaced ( q = +1) to form the defect system.…”

Thorium‐Doped Lithium Fluoride Single Crystal: A Potential Promising Candidate for Solid State Nuclear Optical Clock Materials

“…The formation energies of defect Models 1–5 that only use the cationic vacancy ([V Li ] − ) as the charge compensation mechanism range from 4.87 to 6.08 eV and these are comparable to that of some similar defect configurations. [ 32 ] For Models 6–8 containing interstitial F ([F in ] − ), it is need noted that the formation energies given here correspond to $${\mu _{{\rm{Li}}}} = {\mu _{{\rm{Li\_bulk}}}}$$ and $${\mu _{\rm{F}}} = {\mu _{{\rm{F\_gas}}}}$$ simultaneously, which is different from Models 1–5. Such conditions are difficult to meet experimentally, so although it seems that the formation energies of models 6–8 are lower, it is difficult to obtain this value experimentally.…”

“…Referring to the research on nonequilibrium valence doping, the cationic vacancy of the matrix crystal is a good charge compensation mechanism. [32,[39][40][41][42] Here, Li vacancy ([V Li ] − ) was selected as the charge compensation mechanism of [Th Li ] 3+ substitution defect, and according to the spatial orientation relationship between Li vacancy and Th ion, we excluded some equivalent defect configurations and constructed five 3[V Li ] − -[Th Li ] 3+ defect cluster models. In addition, the charge compensation mechanisms related to interstitial F ([F in ] − ) were also considered.…”

“…[31], which considered the crystal radii with different coordination; b) Taken from ref. [32]; c) Taken from ref. [33]; d) Taken from ref.…”

“…To balance the computing time, computing accuracy, and computing enforceability, we finally calculated the band structure of the 2 × 2 × 2 supercell models at Г point only, and similar parameters are used in the literature. [ 32 ] The approximate separation between k ‐points used in band structure calculation is 0.005 Å −1 . For the DOS calculations that required relatively fewer computing resources, we still used the 4 × 4 × 4 sampling mesh parameters for the k ‐point.…”