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Using Neural Network models to estimate stellar ages from lithium equivalent widths: An EAGLES expansion (2024)
Journal Article
Weaver, G., Jeffries, R. D., & Jackson, R. J. (in press). Using Neural Network models to estimate stellar ages from lithium equivalent widths: An EAGLES expansion. Monthly Notices of the Royal Astronomical Society, https://doi.org/10.1093/mnras/stae2133

We present an Artificial Neural Network (ANN) model of photospheric lithium depletion in cool stars (3000 < Teff/K < 6500), producing estimates and probability distributions of age from 7Li 6708Å equivalent width (LiEW) and effective temperatur... Read More about Using Neural Network models to estimate stellar ages from lithium equivalent widths: An EAGLES expansion.

The Gaia-ESO Survey: 3D dynamics of young groups and clusters from GES and Gaia EDR3 (2024)
Journal Article
Wright, N. J., Jeffries, R. D., Jackson, R. J., Sacco, G. G., Arnold, B., Franciosini, E., …Worley, C. C. (2024). The Gaia-ESO Survey: 3D dynamics of young groups and clusters from GES and Gaia EDR3. Monthly Notices of the Royal Astronomical Society, 533(1), 705–728. https://doi.org/10.1093/mnras/stae1806

We present the first large-scale 3D kinematic study of ∼2700 spectroscopically-confirmed young stars (< 20 Myr) in 18 star clusters and OB associations (hereafter groups) from the combination of Gaia astrometry and Gaia-ESO Survey spectroscopy... Read More about The Gaia-ESO Survey: 3D dynamics of young groups and clusters from GES and Gaia EDR3.

A comparison of oxygen Frenkel formation and rare earth doping in the Lu2SiO5 and Y2SiO5 orthosilicates using a computer modelling approach (2024)
Journal Article
de S. Santos, A. L., B. V. Freire, E., da C. Bispo, G. F., Jackson, R. A., Macedo, Z. S., & E. G. Valerio, M. (2024). A comparison of oxygen Frenkel formation and rare earth doping in the Lu2SiO5 and Y2SiO5 orthosilicates using a computer modelling approach. Computational Materials Science, 243, Article 113125. https://doi.org/10.1016/j.commatsci.2024.113125

The Lu2SiO5 (LSO) and Y2SiO5 (YSO) orthosilicates are well-known in the literature for their properties when doped with rare earth ions. Ce-doped LSO and YSO hosts have been considered as scintillators with high efficiency, but some questions about t... Read More about A comparison of oxygen Frenkel formation and rare earth doping in the Lu2SiO5 and Y2SiO5 orthosilicates using a computer modelling approach.

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.

Local modification of the crystalline structure due to co-doping with RE3+ in cadmium metasilicate (2024)
Journal Article
Freire, E. B. V., Santos, A. L. D. S., Bispo, G. F. D. C., Macedo, Z. S., Jackson, R. A., & Valerio, M. E. G. (2024). Local modification of the crystalline structure due to co-doping with RE3+ in cadmium metasilicate. Ceramics International, 50(13), 22534-22543. https://doi.org/10.1016/j.ceramint.2024.03.355

Persistent emission is a well-known property of cadmium metasilicate (CdSiO3) doped and co-doped with rare earth ions due to the ease of choosing the desired luminescence colour, as well as the possibility of adjusting the emission colour and the lum... Read More about Local modification of the crystalline structure due to co-doping with RE3+ in cadmium metasilicate.

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.

Computer modelling of RbCdF3: Structural and mechanical properties under high pressure, defect disorder and spectroscopic study (2022)
Journal Article
Lucena, J. L. O., de Mesquita, B. R., Santos, R. D. S., Otsuka, A. M., dos Santos, M. A. C., Rezende, M. V. D. S., & Jackson, R. A. (2022). Computer modelling of RbCdF3: Structural and mechanical properties under high pressure, defect disorder and spectroscopic study. Journal of Solid State Chemistry, 312, Article ARTN 123173. https://doi.org/10.1016/j.jssc.2022.123173

In this work, a series of structural and physical properties of the RbCdF3 compound were investigated using atomistic simulation. The effect of hydrostatic pressure on structural and mechanical properties was investigated from 2 to 44 ​GPa and no pha... Read More about Computer modelling of RbCdF3: Structural and mechanical properties under high pressure, defect disorder and spectroscopic study.

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.

Computer modeling of Zircon (ZrSiO4)—Coffinite (USiO4) solid solutions and lead incorporation: Geological implications (2019)
Journal Article
Jackson, & Montenari. (2019). Computer modeling of Zircon (ZrSiO4)—Coffinite (USiO4) solid solutions and lead incorporation: Geological implications. https://doi.org/10.1016/bs.sats.2019.08.005

The structure of zircon, ZrSiO4 is modeled using interatomic potentials. The uranium end-member, coffinite (USiO4) and intermediate solid solutions of zircon and coffinite (UxZr1–xSiO4) are then modeled, allowing the prediction of lattice parameters... Read More about Computer modeling of Zircon (ZrSiO4)—Coffinite (USiO4) solid solutions and lead incorporation: Geological implications.

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.