Research
My research focuses on developing computational methods to investigate the chemical evolution of the universe. By uncovering fundamental reaction mechanisms and molecular processes across diverse astrophysical environments, I aim to gain our understanding of complex organic molecule synthesis and its connection to prebiotic chemistry, providing deeper insights into the origins of life in the universe.
Software
QM/MM: PyQMMM, SICTWO
Electronic structure: Gaussian16, ADF, ORCA
Molecular dynamics: DFTB, TINKER
Periodic DFT: ADF-BAND
Computing
In-house servers:
HPE ProLiant DL360 Gen10 | 40, 64, or 80 CPUs | 256 GB or 320 GB memory | 1.2 TB HDD.
Supercomputers:
C3SE (Gothenburg)
ICR (Kyoto)
Development of computational methods
The chemical reactions are very fast processes (i.e., fs scale), and the lifetime of the intermediates is very short. Therefore, experimental characterisation of the atomic-scale chemical processes is challenging. Modern quantum chemical methods, employing ab-initio computations, offer a way to overcome these limitations. In this direction, I develop an Unbiased Reaction Path Search (URPS) approach to determine complex molecular structures or complex reaction mechanisms.
Also, I develop quantum mechanics/molecular mechanics (QM/MM) methods. In the QM/MM approach, the electronically important part of the molecular system is calculated using a QM method, while the remaining part is calculated using a MM method. The polarizable force fields are an advanced type of computational model used in QM/MM calculations to accurately simulate molecular interactions by incorporating the ability of atoms to change their electronic distributions in response to their environment. The QM/MM implementation in the in-house PyQMMM and SICTWO programs supports various modern polarizable and non-polarizable force fields.
Origin of life in the Universe
Interstellar dust plays a vital role in the formation of molecular clouds—the birthplaces of stars and planets—and contributes to the synthesis of key precursors to biologically relevant molecules. Consequently, understanding the composition, origin, and evolution of dust particles is a central challenge in both astrophysics and astrochemistry. Despite their importance, significant uncertainties remain in all these areas. To address these questions, I employ computational methods to investigate the growth mechanisms of dust particles in the universe and the fundamental chemical reactions occurring on their surfaces that lead to the formation of biologically important molecular building blocks.
Current collaborations: Kirsten Knudsen, Susanne Aalto, and Wouter Vlemmings (Chalmers)
Complex organic molecules (COMs) have been widely detected in the interstellar medium and in diverse protoplanetary environments. Nonetheless, the precise origins of COMs and their potential transformation into prebiotic species, such as amino acids, remain unresolved. The most plausible theory for COM formation under interstellar conditions involves radical-driven chemistry on dust-grain surfaces. Despite substantial progress in observational, experimental, and theoretical astrochemistry, fundamental gaps persist in our mechanistic understanding of these processes. To address these challenges, I utilize quantum chemical approaches to elucidate the pathways and energetics of radical-driven reactions on amorphous ice surfaces at low temperatures (e.g., ~10 K). Also, I investigate the potential roles of ion-mediated processes—both anionic and cationic—as alternative or complementary mechanisms in COM formation.
Current collaborations: Francois Dulieu (CY Cergy Paris Université), Yasuhiro Oba and Naoki Watanabe (Hokkaido)
Design novel catalysis
Transition metal clusters play a pivotal role as catalytic agents in early Earth chemistry, facilitating key chemical transformations that are believed to have contributed to the origin of life. These clusters exhibit the remarkable ability to activate and convert small, inert molecules such as dinitrogen (N₂), carbon dioxide (CO₂), and methane (CH₄) under mild, prebiotic conditions. Through these transformations, they enable the formation of more complex organic compounds, laying the groundwork for biologically relevant chemistry. Quantum chemical investigations of synthetic transition metal clusters provide critical insights into their electronic structure and the fundamental mechanisms underlying their catalytic behavior. By understanding these properties at the molecular level, we can identify design principles that govern their function. My long-term research goal is to leverage this knowledge to develop novel, efficient, and selective catalysts for sustainable chemical technologies.
Current collaborations: Yasuhiro Ohki (Kyoto), Pedro J. Perez (Huelva), Masaharu Nakamura (Kyoto).