Visualization and modeling of energy-structure relationship of Mn4+ in oxides with D4h symmetry based on first-principles calculations and machine learning
(a)Alluqmani Fatimah, (b)Kazuyoshi OGASAWARA
2-1 Gakuen, Sanda 669-1337, JAPAN
Department of Chemistry,
School of Science and Technology,
Kwansei Gakuin University
(a) Student(D1)
(b) Professor
Abstract
Mn4+-doped oxide phosphors have been drawing attention as promising candidates for the red phosphors of white LEDs. However, since the desired emission wavelength has not been realized yet, a theoretical guideline to control the emission energy of Mn4+ in oxides is strongly desired. In this work, in order to clarify the energy-structure relationship of Mn4+ in oxides with D4h symmetry, we performed systematic first-principles calculations of multipllet energies for MnO6 clusters with gradually changed local structures using the discrete variational multi-electron (DVME) method. The variation of multiplet energies depending on two different bond lengths were clearly visualized by creating colored contour maps. In addition, in order to provide an easy-to-use predictive model of the multiplet energies of Mn4+ in oxides, we also performed a machine learning modeling by using the results of the systematic first-principles calculations as the training data. As a result, a simple theoretical model to predict the results of the first-principles calculation of Mn4+ in oxides with D4h symmetry was created. This model would be useful for development of novel Mn4+-doped oxide red phosphors since it enables one to predict the multiplet energies without performing complicated first-principles calculations.
Keywords: phosphor, white LED, first-principles calculation.
Topic: DV-Xa Method