Computational Chemistry Research Unit

In this project, we develop a new reaction theory based on density functional theory (DFT) for figuring out the mechanisms of photo- and electro-chemical reactions and for designing new functional materials by quantum chemistry. Quantum chemistry has extended its applicability with the increase of computer power and plays a inreplaceable role in verifying experimental results. It is one of the main pillars of computational science using K computer. DFT is the main theory of quantum chemistry. For its high parallelization and Order-N efficiency, DFT is better suited for calculations on K computer. However, it has been difficult to apply it to the theoretical analysis of chemical reactions involving electron transfers due to its limited applicability. So far, we have developed long-range correction (LC) scheme to overcome these significant problems of DFT including the charge transfer problem. In this project, we will extend LC-DFT to more practical one by collaborating with experimental and other field theoretical investigators. Using this new theory, we will clarify the mechanisms of significant photo- and electro-chemical reactions and suggest new functional materials.

Research Subjects

• New developments of photo- and electro-chemical reaction theories
• Developments of high-speed computational algorithm of DFT used on K computer
• Reaction mechanism analyses and new functional material designs on

Publications

1. R. Kar, J.-W. Song, T. Sato, and K. Hirao:
   "Long-range corrected density functionals combined with local response dispersion: A promising method for weak interactions"
   J. Comput. Chem
2. J.-W. Song and K. Hirao:
   "Long-range corrected density functional theory with optimized one parameter progressive correlation functional (LC-BOP and LCgau-BOP)"
   Chem. Phys. Lett. (2013) in press, (http://dx.doi.org/10.1016/j.cplett.2013.01.064)
3. R. Kar, J.-W. Song, and K. Hirao
   "Long-range corrected functionals satisfy Koopmans' theorem: calculation of correlation and relaxation energies"
   J. Comput. Chem. (2013) in press, (doi: 10.1002/jcc.23222)
4. R. K. Singh and T. Tsuneda:
   "Reaction Energetics on Long-range Corrected Density Functional Theory: Diels-Alder Reactions"
   J. Comput. Chem., 34, 379-386 (2013)
5. J.-W. Song, K. Yamashita, and K. Hirao:
   "Gaussian attenuation hybrid scheme applied to Ernzerhof-Perdew exchange hole model (Gau-PBEh)"
   J. Chem. Phys. 137, 244105 (2012)
6. S. Suzuki, T. Tsuneda, and K. Hirao:
   "A Theoretical Investigation on Photocatalytic Oxidation on TiO2 surface"
   J. Chem. Phys. 136, 024706(1-6) (2012)
7. J.-W. Song, T. Tsuneda, T. Sato, and K. Hirao:
   "An examination of density functional theories on isomerization energy calculations of organic molecules"
   Theor. Chem. Acc. 130, 851 (2011)
8. J.-W. Song, D. Peng, and K. Hirao:
   "A semiempirical long-range corrected exchange correlation functional including a short-range Gaussian attenuation (LCgau-B97)"
   J. Comput. Chem. 32, 3269 (2011)
9. J.-W. Song, K. Yamashita, and K. Hirao:
   "Communication: A new hybrid exchange correlation functional for band-gap calculations using a short-range Gaussian attenuation (Gaussian-Perdue-Burke-Ernzerhof)"
   J. Chem. Phys. 135, 071103 (2011)
10. A. Nakata, T. Tsuneda, and K. Hirao:
    "Spin-orbit relativistic long-range corrected time-dependent density functional theory for investigating spin-forbidden transitions in photochemical reactions'"
    J. Chem. Phys. 135, 224106(1-9) (2011)