RIKEN Center for Computational Science

OVERVIEW 計算科学研究機構とは

Computational Molecular Science Research Team

Development of a New Molecular Science Based on Original Theorizing and Use of K/Fugaku-Compatible Software

We are chiefly interested in theoretical and computational molecular science based on quantum chemistry. Our main background is molecular orbital theory. In particular, we aim to develop interdisciplinary research that combines quantum chemistry with other research fields such as condensed matter physics and computer science. With the emergence of peta-scale computing platforms, we are entering a new period of modeling. Computer simulations of larger, more complicated, and more realistic systems than ever before can now be carried out. To benefit fully from supercomputers K and Fugaku, we are forging a new molecular science based on original theorizing and employment of our K computer-compatible software that can predict outcomes of molecular experiments.

In leading the way toward a new frontier of theoretical and computational molecular science, the project involves the novel development of theory, algorithms, and software, which will be realized through the collaborative use of K and Fugaku across the fields of computational science and computer science. The specific topics involve: (1) Development of large-scale molecular theory to realize first-principles molecular calculations with tens of thousands of atoms. (2) Development of a highly-accurate molecular theory which is applicable to complicated molecular systems. (3) Development of relativistic molecular theory to accurately treat heavy-element molecular systems. (4) Development of a new program package for molecular theory:“NTChem”. (5) Applications for molecular systems to clarify the mechanism of their chemical reaction and functionality.

Recent Achievements

NTChem: A high-performance software package for quantum molecular simulation
Quantum chemistry software comprises immensely useful tools for material and biological science research. Widely diverse programs have been developed in Western countries, but Japan has lagged behind. Our mission is to provide K/Fugaku users with high-performance software for quantum molecular simulation.

In the early stage of the K computer project, no quantum chemistry software was available for general purpose and massively parallel computation on the K computer. Therefore, we decided to develop NTChem: a comprehensive chemistry software package. NTChem is completely new and implements not only standard quantum chemistry approaches, but also original and improved theoretical methods that we have developed in our research work.

The main features of NTChem are:① electronic structure calculation of the ground state of molecules; ② linear-scaling DFT; ③ excited-state DFT calculation; ④ accurate electron correlation methods for ground and excited states; ⑤ massively parallel computing on supercomputers K and Fugaku in addition to other architectures; ⑥ relativistic electronic structure calculation; ⑦ model calculations for large molecular systems; ⑧ calculation of solvation effects; ⑨ efficient calculation for chemical reaction pathway; ⑩ ab initio molecular dynamics calculation; ⑪ calculation of electric and magnetic properties and ⑫population analysis.

Parallel efficiency of the electron-correlation calculation with NTChem on the K computer


Team Leader Takahito Nakajima

Team Leader
Takahito Nakajima

Biography: Detail
Annual Report
FY2017 (PDF 2MB)
FY2016 (PDF 1MB)
FY2015 (PDF 294KB)
FY2014 (PDF 349KB)
FY2013 (PDF 1.10MB)
FY2012 (PDF 1.39MB)
FY2011 (PDF 495KB)