About the Research
Mapping the reaction paths with the Artificial Force Induced Reaction (AFIR) method
My research topic is to develop a method which explores unknown chemical reaction pathways by using quantum-chemical first-principle calculations and computers. My main calculation method is called ‘Artificial Force-Induced Reaction’ (AFIR), which operates on the principle of including in the calculations an artificial gradient that tries to push reactants together to indicate the position of transition structures on the potential energy surface. Thus we can predict all types of reactions including rearrangements of covalent bonds, hydrogen bonds, coordination bonds, metal-metal bonds, weak bonds of van der Waals interactions, and so on, and can also find pathways of conformational rearrangements, pseudo rotations in organometallic complexes, and those for non-adiabatic transitions between different electronic states.
By repeating this procedure many times, the method can find the whole reaction path network, which tells us the reaction mechanism and uncovers unknown chemical reactions.
In order to effectively find new chemical reactions, we need ideas and verification from experimental chemists. On the other hand, our AFIR method creates a large amount of data, the handling of which already is a serious problem. Therefore, by working together with experimental chemists and information scientists at ICReDD, we will be able to develop a truly useful method for the prediction of chemical reactions.
The Researcher’s Perspective
After high school and way into my university studies, my plan was to become a public servant. However, in my first year as a master student, I remembered a book on computational chemistry I had read with my supervisor, and decided I wanted to give the then-unsolved problem of finding reaction pathways a try. This is when I took the initial steps in what would eventually evolve into AFIR. I enjoyed this work very much, I simply couldn’t quit, and so I decided to become a scientist.
Representative Research Achievements
- Systematic Exploration of the Mechanism of Chemical Reactions: the Global Reaction Route Mapping (GRRM) Strategy using the ADDF and AFIR Methods
S. Maeda, K. Ohno, K. Morokuma, Phys. Chem. Chem. Phys., 2013, 15, 3683-3701
DOI : 10.1039/C3CP44063J
- Finding Reaction Pathways of Type A + B → X: Toward Systematic Prediction of Reaction Mechanisms
S. Maeda, K. Morokuma, J. Chem. Theory Comput., 2011, 7, 2335-2345
DOI : 10.1021/ct200290m
- Finding Reaction Pathways for Multicomponent Reactions: The Passerini Reaction is a Four-component Reaction
S. Maeda, S. Komagawa, M. Uchiyama, K. Morokuma, Angew. Chem. Int. Ed., 2011, 50, 644-649
DOI : 10.1002/anie.201005336
- No Straight Path: Roaming in both Ground- and Excited-state Photolytic Channels of NO3 → NO+O2
M. P. Grubb, M. L. Warter, H.-Y. Xiao, S. Maeda, K. Morokuma, S. W. North, Science, 2012, 335, 1075-1078
DOI : 10.1126/science.1216911
- Intrinsic Reaction Coordinate: Calculation, Bifurcation, and Automated Search
S. Maeda, Y. Harabuchi, Y. Ono, T. Taketsugu, K. Morokuma, Int. J. Quant. Chem., 2015, 115, 258-269
DOI : 10.1002/qua.24757
- Chiral lanthanide lumino-glass for a circularly polarized light security device
- A new tool to create chemical complexity from fatty acids
- Kinetic prediction of reverse intersystem crossing in organic donor–acceptor molecules
- Novel computer-assisted chemical synthesis method cuts research time and cost
- Next-generation medication: where chemistry meets computation