Recent applications of discrete variational multi-electron method
Kazuyoshi Ogasawara
Department of Chemistry, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, JAPAN
Abstract
The discrete variational multi-electron (DVME) program is a first-principles many-electron calculation program especially designed to calculate multiplet states of transition-metal ions and rare-earth ions in crystals. It is a configuration interaction calculation program based on the discrete-variational Xa cluster method. It has been applied to analyze various optical materials such as ruby, alexandrite, Mn4+-doped fluorides and RE-doped YLF. The variety of multiplet spectra such as d-d, f-f, f-d spectra, and X-ray absorption near-edge structures have been reproduced without any empirical parameters and the origins of the peaks in the spectra have been clarified based on the configuration analysis of the many-electron wave functions. The DVME method have been also utilized to create various energy-structure maps for Mn4+ and Ce3+ in oxides which can be used for theoretical design of novel red phosphor materials for white LEDs. Since systematic first-principles calculations are quite time consuming, we have also begun to create simple predictive models based on machine learning by using the results of the first-principles calculations as the training data. This could accelerate the creation of detailed energy-structure maps. In this presentation, I will show some of the recent applications and future perspective of the DVME method
Keywords: First-principles calculation, multiplet, phosphor, machine learning
Topic: DV-Xa Method