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Defects and Spectroscopic Investigation of Eu3+ Doping in MgGa2O4 (2024)
Journal Article
Sousa, M. F., de Mesquita, B. R., Oliveira, J. L., Silva, C. H. P., Tavares, F. J. R., Santos, R. D. S., …Jackson, R. A. (in press). Defects and Spectroscopic Investigation of Eu3+ Doping in MgGa2O4. physica status solidi (b), Article 2300580. https://doi.org/10.1002/pssb.202300580

Atomistic simulation is performed to study the defect properties and spectroscopy in the MgGa2O4 structure. The calculations indicate that the most favorable type of intrinsic defect is generated by the cation antisite defect, in which there is an ex... Read More about Defects and Spectroscopic Investigation of Eu3+ Doping in MgGa2O4.

Effect of trivalent rare earth doping in cadmium silicates hosts: a theoretical study (2022)
Journal Article
Santos, A., Bispo, G., Freire, E., Macedo, Z., Jackson, R., & Valerio, M. (2022). Effect of trivalent rare earth doping in cadmium silicates hosts: a theoretical study. Physica Scripta, https://doi.org/10.1088/1402-4896/aca228

The objective of the present work is to investigate the possibilities for extrinsic defects in the three cadmium silicate matrices, CdSiO3, Cd2SiO4 and Cd3SiO5 and understand the final geometry of the most energetically favourable defects, which are... Read More about Effect of trivalent rare earth doping in cadmium silicates hosts: a theoretical study.

Defects in MgB4O7 (pure and doped with lanthanides): A case study using a computational modelling approach (2022)
Journal Article
Bispo, G., Nascimento, D., Santana, L., Ferreira, G., Macedo, Z., Lima, H., …Valerio, M. (2022). Defects in MgB4O7 (pure and doped with lanthanides): A case study using a computational modelling approach. Physica B: Condensed Matter, 1-9. https://doi.org/10.1016/j.physb.2022.414049

Lanthanide-doped MgB4O7 is a potential dosimetric material due to its thermoluminescence (TL) and optically stimulated luminescence (OSL) properties. These properties have been largely reported, but there are few theoretical studies dedicated to unde... Read More about Defects in MgB4O7 (pure and doped with lanthanides): A case study using a computational modelling approach.

Optical spectroscopy study of Eu-doped ions in BaAl2O4 phosphors (2021)
Journal Article
Rezende, M. D. S., Valerio, M., Araujo, R., Jackson, R., dos Santos Mattos, E., & dos Santos Junior, B. (2021). Optical spectroscopy study of Eu-doped ions in BaAl2O4 phosphors. Journal of Luminescence, 1-5. https://doi.org/10.1016/j.jlumin.2021.118011

Computational and experimental methodology is employed to study optical properties in Eu-doped BaAl2O4 phosphors. The symmetry and detailed geometry of the Eu-dopant site, predicted by atomistic simulation, are used to calculate the crystal field par... Read More about Optical spectroscopy study of Eu-doped ions in BaAl2O4 phosphors.

Intrinsic defects and non-stoichiometry in undoped cadmium silicate hosts (2021)
Journal Article
Vaz Freire, E., de Sales Santos, A., da Cunha Bispo, G., Macedo, Z., Gomes, M., Giroldo Valerio, M., & Jackson, R. (2021). Intrinsic defects and non-stoichiometry in undoped cadmium silicate hosts. Journal of Alloys and Compounds, https://doi.org/10.1016/j.jallcom.2020.157580

Cadmium silicates, mainly the CdSiO3 phase, are interesting materials due to their persistent and intrinsic luminescence, making them possible candidates for a number of applications. Although many of the luminescence properties of these materials ar... Read More about Intrinsic defects and non-stoichiometry in undoped cadmium silicate hosts.

Computer modelling of Bi12SiO20 and Bi4Si3O12: Intrinsic defects and rare earth ion incorporation (2020)
Journal Article
Jackson. (2020). Computer modelling of Bi12SiO20 and Bi4Si3O12: Intrinsic defects and rare earth ion incorporation. Journal of Solid State Chemistry, https://doi.org/10.1016/j.jssc.2020.121608

Defect properties of Bi12SiO12 and Bi4Si3O12 compounds were investigated using atomistic computer modelling techniques based on energy minimisation. Interatomic potentials obtained by empirical fitting reproduce the lattice parameters for both materi... Read More about Computer modelling of Bi12SiO20 and Bi4Si3O12: Intrinsic defects and rare earth ion incorporation.

Computer Simulation of the Incorporation of V2+, V3+, V4+, V(5+)and Mo3+, Mo4+, Mo5+, Mo(6+)Dopants in LiNbO3 (2020)
Journal Article
Jackson. (2020). Computer Simulation of the Incorporation of V2+, V3+, V4+, V(5+)and Mo3+, Mo4+, Mo5+, Mo(6+)Dopants in LiNbO3. Crystals, https://doi.org/10.3390/cryst10060457

The doping of LiNbO(3)with V2+, V3+, V(4+)and V(5+)as well as Mo3+, Mo4+, Mo(5+)and Mo(6+)ions is of interest in enhancing its photorefractive properties. In this paper, possible incorporation mechanisms for these ions in LiNbO(3)are modelled, using... Read More about Computer Simulation of the Incorporation of V2+, V3+, V4+, V(5+)and Mo3+, Mo4+, Mo5+, Mo(6+)Dopants in LiNbO3.

Site-selective laser spectroscopy and defect configurations of the Nd3+-Li+ centres in ZnO powders (2020)
Journal Article
Jackson. (2020). Site-selective laser spectroscopy and defect configurations of the Nd3+-Li+ centres in ZnO powders. Journal of Alloys and Compounds, 153306 - 153306. https://doi.org/10.1016/j.jallcom.2019.153306

Near-infrared emission in the 885–915?nm region was observed for two distinct Nd3+ centres that co-exist in hexagonal wurtzite ZnO:1?mol%Nd3+:10?mol%Li+ powders. The powder samples were prepared by sintering in air at 950?°C and the emission, attribu... Read More about Site-selective laser spectroscopy and defect configurations of the Nd3+-Li+ centres in ZnO powders.

Ln3+ doping in CaYAl3O7 and luminescence concentration quenching studied via a new computer modelling strategy (2019)
Journal Article
Jackson. (2019). Ln3+ doping in CaYAl3O7 and luminescence concentration quenching studied via a new computer modelling strategy. Optical Materials, 212-216. https://doi.org/10.1016/j.optmat.2019.04.036

Ln-doped CaYAl3O7 (CYAM) has several applications due to its optical properties. This crystal matrix belongs to the melilite family, where Ca2+/Y3+ ions are randomly distributed at the same crystallographic site keeping a composition ratio of 1:1. Th... Read More about Ln3+ doping in CaYAl3O7 and luminescence concentration quenching studied via a new computer modelling strategy.

A computational and spectroscopic study of Dy3+ doped BaAl2O4 phosphors (2018)
Journal Article
Jackson. (2018). A computational and spectroscopic study of Dy3+ doped BaAl2O4 phosphors. Optical Materials, 328 - 332. https://doi.org/10.1016/j.optmat.2018.06.039

Computational and experimental methods are employed to study the optical properties of Dy-doped BaAl2O4 matrix. Atomistic modelling is used to make predictions of Dy doping sites and charge compensation schemes. The symmetry predicts from atomistic m... Read More about A computational and spectroscopic study of Dy3+ doped BaAl2O4 phosphors.

The Gaia-ESO Survey: a kinematical and dynamical study of four young open clusters (2018)
Journal Article
Jeffries, R., Jackson, R., & Wright, N. (2018). The Gaia-ESO Survey: a kinematical and dynamical study of four young open clusters. Astronomy & Astrophysics, https://doi.org/10.1051/0004-6361/201832645

Context The origin and dynamical evolution of star clusters is an important topic in stellar astrophysics. Several models have been proposed in order to understand the formation of bound and unbound clusters and their evolution, and they can be test... Read More about The Gaia-ESO Survey: a kinematical and dynamical study of four young open clusters.

Modelling of Intrinsic Defects in CaYAl3O7 (2018)
Journal Article
da C. Bispo, G., Jackson, R., & Valerio, M. (2018). Modelling of Intrinsic Defects in CaYAl3O7. Acta Physica Polonica A, 133(4), 781-784. https://doi.org/10.12693/aphyspola.133.781

CaYAl3O7 presents a challenge for computer modelling techniques because of its site-occupancy disorder related to the Ca/Y shared site. Supercells were built to reproduce experimental results which have the best agreement and lowest lattice energy. T... Read More about Modelling of Intrinsic Defects in CaYAl3O7.

Computer modelling of hafnium doping in lithium niobate (2018)
Journal Article
Jackson, R., Valerio, M., & Araujo, R. (2018). Computer modelling of hafnium doping in lithium niobate. Crystals, 123. https://doi.org/10.3390/cryst8030123

Lithium niobate, LiNbO3, is an important technological material with good electro-optic, acousto-optic, elasto-optic, piezoelectric and nonlinear properties. Doping LiNbO3 with hafnium, Hf has been shown to improve the resistance of the material to o... Read More about Computer modelling of hafnium doping in lithium niobate.

Computer modelling of double doped SrAl2O4 for phosphor applications (2017)
Journal Article
Jackson, R. A., Kavanagh, L. A., & Snelgrove, R. A. (2017). Computer modelling of double doped SrAl2O4 for phosphor applications. IOP Conference Series: Materials Science and Engineering, 169, Article 012004. https://doi.org/10.1088/1757-899x/169/1/012004

This paper describes a modelling study of SrAl2O4, which has applications as a phosphor material when doped with Eu2+ and Dy3+ ions. The procedure for modelling the pure and doped material is described and then results are presented for the single an... Read More about Computer modelling of double doped SrAl2O4 for phosphor applications.

Computer simulation of metal co-doping in lithium niobate (2014)
Journal Article
Araujo, R. M., Valerio, M. E. G., & Jackson, R. A. (2014). Computer simulation of metal co-doping in lithium niobate. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 470(2171), Article 20140406. https://doi.org/10.1098/rspa.2014.0406

Lithium niobate, LiNbO3, is an important technological material with good electro-optic, acousto-optic, elasto-optic, piezoelectric and nonlinear properties. Computer modelling provides a useful means of determining the properties of the material, in... Read More about Computer simulation of metal co-doping in lithium niobate.

Tantalum and niobium diffusion in single crystalline lithium niobate (2014)
Journal Article
Fielitz, P., Borchardt, G., Ganschow, S., Bertram, R., Jackson, R., Fritze, H., & Becker, K. (2014). Tantalum and niobium diffusion in single crystalline lithium niobate. Solid State Ionics, 259, 14-20. https://doi.org/10.1016/j.ssi.2014.02.005

LiNbO3 and LiTaO3 are isomorphous and Nb and Ta have the same valence electron configuration and the same ionic radii. This suggests the use of Ta as a tracer to probe the self-diffusion of Nb in LiNbO3. The diffusion system consisted of a 20 nm laye... Read More about Tantalum and niobium diffusion in single crystalline lithium niobate.