Crystal-field hamiltonian and spin–orbit interaction for d2 and d8 ions at low C3 symmetry sites: V3+:Al2O3 and Ni2+:LiNbO3

Kammoun, S.; Souissi, Hajer; Elleuch, Riadh; Dammak, M.; Kamoun, Mohamed

doi:10.1016/j.jlumin.2008.11.019

Cited by 10 publications

(3 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The 3d 8 electron configuration of Ni 2+ is usually affected by the crystal field. The Tanabe–Sugano energy level diagram can be used to represent the energy level splitting of Ni 2+ in an octahedral field (Figure e), and the intensity parameter D q / B of the crystal field can be calculated by the following formula , according to the spectral data: D q = v 1 10 B = false( v 3 − 2 v 1 false) · false( v 3 − v 1 false) 3 false( 5 v 3 − 9 v 1 false) …”

Section: Resultsmentioning

confidence: 99%

Strategy of Charge Compensation for High-Performance Ni²⁺-Activated MgAl₂O₄ Spinel Near-Infrared Phosphor Synthesis via the Sol–Gel Combustion Method

Deng,

Zhu,

Gao

et al. 2024

Inorg. Chem.

View full text Add to dashboard Cite

Near-infrared (NIR) phosphor conversion light-emitting diodes (pc-LEDs) have great application potential as NIR light sources in many fields such as food analysis, night vision illumination, and bioimaging for noninvasive medical diagnosis. In general, phosphors synthesized by a high-temperature solidphase method have large particle sizes and have to be processed to fine powders by a grinding process, which may introduce surface defects and lower the luminous efficiency. Here, we report a sol−gel sintering method with ammonium nitrate and citric acid as the sacrificing agents to synthesize high purity, nanosized (less than 50 nm) Zr 4+ /Ni 2+ codoped MgAl 2 O 4 spinel NIR phosphors, in which MgAl 2 O 4 spinel is the matrix, Ni 2+ is the luminous center, and Zr 4+ acts as the charge compensator. We systematically characterized the crystal structures and NIR luminescence properties of the Ni 2+ -doped MgAl 2 O 4 and the Zr 4+ /Ni 2+ codoped MgAl 2 O 4 . Under 390 nm light excitation, the emission spectrum of the Ni 2+ -doped MgAl 2 O 4 phosphor covers 900−1600 nm, the half-peak width is 251 nm, and the peak position is located at 1230 nm. We demonstrated that by incorporating small amounts of Zr 4+ as the charge compensator, the NIR emission intensity of the Zr 4+ /Ni 2+ codoped MgAl 2 O 4 nanosized phosphor was doubled over that of the Ni 2+ -doped MgAl 2 O 4 phosphor. The optimal content of the charge compensator was 2 mol %. More importantly, the inclusion of Zr 4+ led to a NIR phosphor with improved thermal stability in luminous properties, and the luminous intensity measured at 100 °C was 33.83% of that measured at room temperature (20 °C). This study demonstrates that NIR phosphor nanomaterials with high-purity and enhanced optical properties can be designed and synthesized through the charge compensation strategy by a sol−gel sintering method.

show abstract

Section: Resultsmentioning

confidence: 99%

Strategy of Charge Compensation for High-Performance Ni²⁺-Activated MgAl₂O₄ Spinel Near-Infrared Phosphor Synthesis via the Sol–Gel Combustion Method

Deng,

Zhu,

Gao

et al. 2024

Inorg. Chem.

View full text Add to dashboard Cite

show abstract

“…These are confirmed by the facts that experimental spectra of Cr 4+ and V 3+ in ¡-Al 2 O 3 are well described by assuming these cations to occupy the distorted octahedral symmetry sites. [23][24][25] Since TM ion substitutes Al site, the structure thus should be relaxed to be more stable. We prepare a 2 © 2 © 2 rhombohedral supercell (80 atoms/cell) including one TM per super cell.…”

Section: Qsgw Calculations Of Crmentioning

confidence: 99%

“…Structure optimizations of both unit cell volume and atomic positions are performed by projected augmented wave method implemented in Quantum ESPRESSO package. 25,26) The cut off energy is 60 Ry, and k-point mesh is 6 © 6 © 6. We extracted 1 © 1 © 1 local structure around TM ion from the optimized supercell for QSGW electronic calculations due to its high computational cost.…”

Section: Qsgw Calculations Of Crmentioning

confidence: 99%

Quasiparticle Self-Consistent GW Analysis of Excited States and Model Construction of 3d2 Luminescent Centers in α-Aluminum Oxide

Saito,

Suzuki,

Sato

et al. 2023

Mater. Trans.

View full text Add to dashboard Cite

Cr 4+ -doped crystals are promising materials for infrared solid laser applications. In order to choose proper host materials of Cr 4+ from the wide variety of crystals, multiplet energy levels of Cr 4+ should be evaluated without experimental information. A newly developed firstprinciples method for determining the mean-field Hamiltonian of the localized luminescent center based on quasiparticle self-consistent GW was applied to 3d 2 transition metal ions (Cr 4+ and V 3+ ) in ¡-Al 2 O 3 . Our method gave good agreement with the effective Coulomb parameters and crystal-field parameters estimated from experimental data. Multiplet energy structures were therefore well reproduced by our method. These results show the possibility of designing new laser host materials within the framework of the first-principles calculations.

show abstract

Synthesis, structural and optical characterization of LiNbO3 material for optical applications

Guithi

Sekrafi

Kharrat

et al. 2023

J Opt

View full text Add to dashboard Cite

Crystal-field hamiltonian and spin–orbit interaction for d2 and d8 ions at low C3 symmetry sites: V3+:Al2O3 and Ni2+:LiNbO3

Cited by 10 publications

References 34 publications

Strategy of Charge Compensation for High-Performance Ni²⁺-Activated MgAl₂O₄ Spinel Near-Infrared Phosphor Synthesis via the Sol–Gel Combustion Method

Strategy of Charge Compensation for High-Performance Ni²⁺-Activated MgAl₂O₄ Spinel Near-Infrared Phosphor Synthesis via the Sol–Gel Combustion Method

Quasiparticle Self-Consistent <i>GW</i> Analysis of Excited States and Model Construction of 3<i>d</i><sup>2</sup> Luminescent Centers in α-Aluminum Oxide

Synthesis, structural and optical characterization of LiNbO3 material for optical applications

Contact Info

Product

Resources

About

Crystal-field hamiltonian and spin–orbit interaction for d2 and d8 ions at low C3 symmetry sites: V3+:Al2O3 and Ni2+:LiNbO3

Cited by 10 publications

References 34 publications

Strategy of Charge Compensation for High-Performance Ni2+-Activated MgAl2O4 Spinel Near-Infrared Phosphor Synthesis via the Sol–Gel Combustion Method

Strategy of Charge Compensation for High-Performance Ni2+-Activated MgAl2O4 Spinel Near-Infrared Phosphor Synthesis via the Sol–Gel Combustion Method

Quasiparticle Self-Consistent <i>GW</i> Analysis of Excited States and Model Construction of 3<i>d</i><sup>2</sup> Luminescent Centers in α-Aluminum Oxide

Synthesis, structural and optical characterization of LiNbO3 material for optical applications

Contact Info

Product

Resources

About

Strategy of Charge Compensation for High-Performance Ni²⁺-Activated MgAl₂O₄ Spinel Near-Infrared Phosphor Synthesis via the Sol–Gel Combustion Method

Strategy of Charge Compensation for High-Performance Ni²⁺-Activated MgAl₂O₄ Spinel Near-Infrared Phosphor Synthesis via the Sol–Gel Combustion Method