STATE (Simulation Tool for Atom TEchnology)

Development of first-principles molecular dynamics program code and its application to material sciences


1. Heterogeneous Catalysis.

In the research of heterogeneous catalysis, it is of crucial importance to identify the catalytically active sites, but it is usually a difficult problem. First-principles molecular dynamics simulation reproduces reaction environment such as temperature, structure and so on as close to those of the real world as possible. Close comparison between simulated and experimental results enables us not only to confirm the experimental results but also to understand important factors which determine the reactivity and selectivity of catalysts. Recently, I study methanol synthesis on Cu surfaces and reactivity of TiO2 surfaces. Both systems are industrially important.

2. Self-assembled monolayers on Au

Organic thin films on solid surfaces have been attracting enormous Attention due to a very wide range of potential applications, running from catalysis, to molecular recognition, to nanoscale electronic devices, etc. Among them, alkanethiols and dialkyl disulfides on gold are the most intensively studied systems because they are simple, stable and easy to prepare. The adsorption states of those molecules, however, are still a matter of intense debate. I am studying alkanethiol adsorbed Au(111) surfaces using first-principles molecular dynamics techniques and clarifying the structural problem of the system.

Recent Publications:

1. Y. Morikawa, K. Iwata, J. Nakamura, T. Fujitani and K. Terakura, "Ab initio study of surface structural changesduring methanol synthesis over Zn/Cu(111)", Chem. Phys. Lett., 304 91-97 (1999).

2. M. Boero, Y. Morikawa, K. Terakura and M. Ozeki, "First principles study of thermal decomposition of alkyl-gallium and tertiarybutylarsine", J. Chem. Phys., 112 9549-9556 (2000).

3. Y. Morikawa, K. Iwata, and K. Terakura, "First-principles study of chemical reactions at metal surfaces", RIKEN Review, 29 9-11 (2000).

4. Y. Morikawa, K. Iwata and K. Terakura, "Theoretical study of hydrogenation process of formate on clean and Zn deposited Cu(111) surfaces", Appl. Surf. Sci., 169-179 11-15 (2001).

5. Y. Morikawa, "Adsorption geometries and vibrational modes of C2H2 on the Si(001) surface", Phys. Rev. B 63 033405 (2001).

6. T. Hayashi, Y. Morikawa and H. Nozoye, "Evidence of adsorption as thiolate at the bridge site: Adsorption state of dimethyl disulfide on Au(111)", J. Chem. Phys., vol. 114 p. 7615-7621 (2001).

7. S. Masuda, R. Suzuki, M. Aoki, Y. Morikawa, R. Kishi, and M. Kawai, "Spatial electron distribution of CO adsorbed on Ni(100) and Ni(111) surfaces probed by metastable impact electron spectroscopy", J. Chem. Phys., vol. 114, p. 8546-8554 (2001).