TY  - JOUR
AU  - Zou, Wei
AU  - Lou, Bibo
AU  - Kurboniyon, Mekhrdod S.
AU  - Buryi, Maksym
AU  - Rahimi, Farhod
AU  - Srivastava, Alok M.
AU  - Brik, Mikhail G.
AU  - Wang, Jing
AU  - Ma, Chonggeng
PY  - 2024
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/13187
AB  - In this study, we conducted an extensive investigation into broadband near-infrared luminescence of Cr3+-doped Ca3Y2Ge3O12 garnet, employing first-principles calculations within the density functional theory framework. Our initial focus involved determining the site occupancy of Cr3+ activator ions, which revealed a pronounced preference for the Y3+ sites over the Ca2+ and Ge4+ sites, as evidenced by the formation energy calculations. Subsequently, the geometric structures of the excited states 2E and 4T2, along with their optical transition energies relative to the ground state 4A2 in Ca3Y2Ge3O12:Cr3+, were successfully modeled using the ΔSCF method. Calculation convergence challenges were effectively addressed through the proposed fractional particle occupancy schemes. The constructed host-referred binding energy diagram provided a clear description of the luminescence kinetics process in the garnet, which explained the high quantum efficiency of emission. Furthermore, the accurate prediction of thermal excitation energy yielded insights into the thermal stability of the compound, as illustrated in the calculated configuration coordinate diagram. More importantly, all calculated data were consistently aligned with the experimental results. This research not only advances our understanding of the intricate interplay between geometric and electronic structures, optical properties, and thermal behavior in Cr3+-doped garnets but also lays the groundwork for future breakthroughs in the high-throughput design and optimization of luminescent performance and thermal stability in Cr3+-doped phosphors.
T2  - Materials
T1  - Unraveling Broadband Near-Infrared Luminescence in Cr3+-Doped Ca3Y2Ge3O12 Garnets: Insights from First-Principles Analysis
VL  - 17
IS  - 7
SP  - 1709
DO  - 10.3390/ma17071709
ER  - 

@article{
author = "Zou, Wei and Lou, Bibo and Kurboniyon, Mekhrdod S. and Buryi, Maksym and Rahimi, Farhod and Srivastava, Alok M. and Brik, Mikhail G. and Wang, Jing and Ma, Chonggeng",
year = "2024",
abstract = "In this study, we conducted an extensive investigation into broadband near-infrared luminescence of Cr3+-doped Ca3Y2Ge3O12 garnet, employing first-principles calculations within the density functional theory framework. Our initial focus involved determining the site occupancy of Cr3+ activator ions, which revealed a pronounced preference for the Y3+ sites over the Ca2+ and Ge4+ sites, as evidenced by the formation energy calculations. Subsequently, the geometric structures of the excited states 2E and 4T2, along with their optical transition energies relative to the ground state 4A2 in Ca3Y2Ge3O12:Cr3+, were successfully modeled using the ΔSCF method. Calculation convergence challenges were effectively addressed through the proposed fractional particle occupancy schemes. The constructed host-referred binding energy diagram provided a clear description of the luminescence kinetics process in the garnet, which explained the high quantum efficiency of emission. Furthermore, the accurate prediction of thermal excitation energy yielded insights into the thermal stability of the compound, as illustrated in the calculated configuration coordinate diagram. More importantly, all calculated data were consistently aligned with the experimental results. This research not only advances our understanding of the intricate interplay between geometric and electronic structures, optical properties, and thermal behavior in Cr3+-doped garnets but also lays the groundwork for future breakthroughs in the high-throughput design and optimization of luminescent performance and thermal stability in Cr3+-doped phosphors.",
journal = "Materials",
title = "Unraveling Broadband Near-Infrared Luminescence in Cr3+-Doped Ca3Y2Ge3O12 Garnets: Insights from First-Principles Analysis",
volume = "17",
number = "7",
pages = "1709",
doi = "10.3390/ma17071709"
}

Zou, W., Lou, B., Kurboniyon, M. S., Buryi, M., Rahimi, F., Srivastava, A. M., Brik, M. G., Wang, J.,& Ma, C.. (2024). Unraveling Broadband Near-Infrared Luminescence in Cr3+-Doped Ca3Y2Ge3O12 Garnets: Insights from First-Principles Analysis. in Materials, 17(7), 1709.
https://doi.org/10.3390/ma17071709

Zou W, Lou B, Kurboniyon MS, Buryi M, Rahimi F, Srivastava AM, Brik MG, Wang J, Ma C. Unraveling Broadband Near-Infrared Luminescence in Cr3+-Doped Ca3Y2Ge3O12 Garnets: Insights from First-Principles Analysis. in Materials. 2024;17(7):1709.
doi:10.3390/ma17071709 .

Zou, Wei, Lou, Bibo, Kurboniyon, Mekhrdod S., Buryi, Maksym, Rahimi, Farhod, Srivastava, Alok M., Brik, Mikhail G., Wang, Jing, Ma, Chonggeng, "Unraveling Broadband Near-Infrared Luminescence in Cr3+-Doped Ca3Y2Ge3O12 Garnets: Insights from First-Principles Analysis" in Materials, 17, no. 7 (2024):1709,
https://doi.org/10.3390/ma17071709 . .

TY  - JOUR
AU  - Kurboniyon, Mekhrdod S.
AU  - Lou, Bibo
AU  - Zafari, Umar
AU  - Rahimi, Farhod
AU  - Srivastava, Alok M.
AU  - Yamamoto, Tomoyuki
AU  - Brik, Mikhail G.
AU  - Ma, Chong-Geng
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/11381
AB  - In this study, we present the results of first-principles calculations conducted within the density functional theory to investigate the geometric and electronic structures of the ground 4 A2 and excited 2 E and 4 T2 states, as well as the optical transition energies between these states, in the prototype system of K2SiF6:Mn4+. To achieve this, we employed a comprehensive evaluation of the five representative exchange-correlation functionals, enabling the development of a state-of-art calculation scheme that effectively describes the geometric and electronic structures of the excited 2 E and 4 T2 states. The calculated excitation, emission and zero-phonon line energies of the optical transitions between the ground 4 A2 state and the excited 2 E and 4 T2 states demonstrate a better agreement with experimental results. However, we observed that the conventional and widely-used approach based on the analysis of the electronic density of states diagrams derived from the ground state calculations failed to accurately evaluate the vertical optical transition energies from the 4 A2 ground state to the excited 2 E and 4 T2 states when compared to experimental data. The calculation technique developed in this study holds the potential for widespread application to other combinations of host materials and impurity ion, which is of great importance for future developments in the field of optical materials.
T2  - Journal of Luminescence
T1  - First-principles study of geometric and electronic structures, and optical transition energies of Mn4+ impurity ions: K2SiF6 as a prototype
VL  - 263
SP  - 120103
DO  - 10.1016/j.jlumin.2023.120103
ER  - 

@article{
author = "Kurboniyon, Mekhrdod S. and Lou, Bibo and Zafari, Umar and Rahimi, Farhod and Srivastava, Alok M. and Yamamoto, Tomoyuki and Brik, Mikhail G. and Ma, Chong-Geng",
year = "2023",
abstract = "In this study, we present the results of first-principles calculations conducted within the density functional theory to investigate the geometric and electronic structures of the ground 4 A2 and excited 2 E and 4 T2 states, as well as the optical transition energies between these states, in the prototype system of K2SiF6:Mn4+. To achieve this, we employed a comprehensive evaluation of the five representative exchange-correlation functionals, enabling the development of a state-of-art calculation scheme that effectively describes the geometric and electronic structures of the excited 2 E and 4 T2 states. The calculated excitation, emission and zero-phonon line energies of the optical transitions between the ground 4 A2 state and the excited 2 E and 4 T2 states demonstrate a better agreement with experimental results. However, we observed that the conventional and widely-used approach based on the analysis of the electronic density of states diagrams derived from the ground state calculations failed to accurately evaluate the vertical optical transition energies from the 4 A2 ground state to the excited 2 E and 4 T2 states when compared to experimental data. The calculation technique developed in this study holds the potential for widespread application to other combinations of host materials and impurity ion, which is of great importance for future developments in the field of optical materials.",
journal = "Journal of Luminescence",
title = "First-principles study of geometric and electronic structures, and optical transition energies of Mn4+ impurity ions: K2SiF6 as a prototype",
volume = "263",
pages = "120103",
doi = "10.1016/j.jlumin.2023.120103"
}

Kurboniyon, M. S., Lou, B., Zafari, U., Rahimi, F., Srivastava, A. M., Yamamoto, T., Brik, M. G.,& Ma, C.. (2023). First-principles study of geometric and electronic structures, and optical transition energies of Mn4+ impurity ions: K2SiF6 as a prototype. in Journal of Luminescence, 263, 120103.
https://doi.org/10.1016/j.jlumin.2023.120103

Kurboniyon MS, Lou B, Zafari U, Rahimi F, Srivastava AM, Yamamoto T, Brik MG, Ma C. First-principles study of geometric and electronic structures, and optical transition energies of Mn4+ impurity ions: K2SiF6 as a prototype. in Journal of Luminescence. 2023;263:120103.
doi:10.1016/j.jlumin.2023.120103 .

Kurboniyon, Mekhrdod S., Lou, Bibo, Zafari, Umar, Rahimi, Farhod, Srivastava, Alok M., Yamamoto, Tomoyuki, Brik, Mikhail G., Ma, Chong-Geng, "First-principles study of geometric and electronic structures, and optical transition energies of Mn4+ impurity ions: K2SiF6 as a prototype" in Journal of Luminescence, 263 (2023):120103,
https://doi.org/10.1016/j.jlumin.2023.120103 . .