ProjectsEducational / Academic Type

Research Overview

We are conducting academic research to transform present “first-principles calculations,” which oversimplifies many-body electron systems, into “true first-principles calculations” that can reliably predict the properties of potentially-useful materials. The fundamental basis of our research is TOMBO (TOhoku Mixed-Basis Orbitals ab initio simulation package), a unique first-principles calculation method that we have been developing for more than 30 years, which can calculate absolute values of energy of material systems and predict time evolution of chemical reactions without experimental/phenomenological parameters. TOMBO can predict the time evolution of chemical reactions with a high degree of confidence.
In addition, we are conducting science and technology education activities for companies, students, and society in general through the “DA-TE Graduate School,” which has accumulated more than 100 recordings of lectures given by emeritus professors of universities.

Research Features

First-principles calculations based on density functional theory, which are widely used in condensed matter physics, theoretical chemistry, pharmacology, materials research, and other fields, commonly fail to identify essential problems due to their ease of use with commercially available software, that require experimental values with parameters. In particular, there are many AI strategies that accumulate a large number of numerical results and use machine learning to predict useful materials, but research on the fundamentals is generally lacking. We are developing our own computational methods with the aim of making fundamental progress in theoretical computation. In particular, TOMBO enables us to calculate absolute values of the energy of material systems, whereas other software can only calculate relative values. TOMBO is the only software in the world that can handle excited states with high accuracy, which is important for tracing chemical reaction processes.

Expected Outcomes and Developments

Density functional theory, proposed by Professor Kohn 60 years ago, succeeded in dramatically reducing computational complexity by replacing the variational for many-body systems of electrons with a density instead of a conventional wave function. However, it only covers the ground state, and the crucial electron exchange-correlation functional cannot be uniquely determined. Therefore, the present situation is that all calculations are made to reproduce experimental values by parameterizing the exchange-correlation functional. We are working to remove this requirement and have already succeeded in simulating molecular hydrogen evolution during the decomposition of methane molecules over catalysts without any experimental parameters to understand the fundamentals of combustion. We are presently working on elucidating the basic elements of DNA recombination, which is expected to contribute to the advancement of our understanding of problems in biological systems. The processing power of the supercomputer continues to increase tenfold every five years according to Moore's Law, and we plan to expand this to handle systems with large numbers of atoms, such as hydration reactions on cement surfaces.

References
1. ”Non-Adiabatic Excited-State Time-Dependent GW (TDGW) Molecular Dynamics Simulation of Nickel-Atom Aided Photolysis of Methane to Produce a Hydrogen Molecule”, Nanomaterials, 2024, 1, 0.
https://doi.org/10.3390/nano1010000.
2. 日刊工業新聞2024年6月21日「第一原理計算に新手法ー東北大など電子励起状態に対応」