Yasuyuki Ishikawa


Yasuyuki IshikawaContact
Office: FB 319 – located on the third floor of Facundo Bueso Bldg
Email: yishikawa@uprrp.edu
Phone: 787-764-0000  ext. 5908

Ph.D., University of Iowa, 1976.
Postdoctoral Fellow, Rutgers University, 1976-78.
Wissenschaftlicher Mitarbeiter, Universität Siegen, Germany, 1978-80.

Research Interests

Relativistic Many-Body Theory; Ab Initio Monte Carlo/Molecular Dynamics Simulation of Many-Body Systems; Theoretical modeling and simulation of electrochemical systems

Research Focus

Relativistic many-body theory for atoms and molecules: Heavy atom species are many-electron systems with complicated state structures which push conventional computational techniques to their limits. During the last two decades, we have been trying to find suitable fully relativistic SCF and many-body theories (e.g., relativistic many-body perturbation theory and relativistic coupled cluster theory) for atoms and molecules as a means of turning physical pictures of electronic systems in which relativistic and QED effects are not negligible into ab initio computational tools, and of extracting from the Dirac relativistic electron theory more nearly correct physical pictures.

Ab initio Monte Carlo/molecular dynamics studies of structure and dynamics of polyatomic systems and solid/liquid interface: The major difficulty in computer simulations of the structure and dynamics of metal, semiconductor and molecular clusters is the description of the many-body interactions. The pair-wise approximation commonly used to describe these systems does not work well for covalent and metallic systems where many-body interactions play a crucial role. We have developed ab initio molecular dynamics and replica Monte Carlo algorithms that describe the many-body interactions in these clusters in terms of ab initio correlated method.

Selected peer-reviewed publications (2009 – 2011)

  1. Atomic lifetime measurements on forbidden transitions of Al-, Si-, P-, and S-like ions at a heavy-ion storage ring, E. Traebert, J. Hoffmann, C. Krantz, A. Wolf, Y. Ishikawa, J. A. Santana, J. Phys. B42 (2009) 025002.
  2. Spinel LiMn2-xNixO4 cathode materials for high energy density lithium ion rechargeable batteries, R. Singhal, José J. Saavedra, Rajesh Katiyar, Yasuyuki Ishikawa, Marius J. Vilkas, S. R. Das, M. S. Tomar and R. S. Katiyar, Journal of Renewable and Sustainable Energy, 1 (2009) 023102.
  3. A Density-functional Theory Study of the Water-gas Shift Mechanism on Pt/Ceria (111), R. T. Kinch, C. R. Cabrera, Y. Ishikawa, J. Phys. Chem. C, 113 (2009) 9239.
  4. Density-Functional Theory Study of Interactions between Water and Carbon Monoxide Adsorbed on Platinum under Electrochemical Conditions, J. A. Santana and Y. Ishikawa, Chem. Phys. Letters, 478 (2009) 110
  5. Benchmarking atomic data for astrophysics: Fe XVII EUV lines, G. Del Zanna andY. Ishikawa, Astronomy and Astrophysics, 508 (2009) 1517.
  6. Separation of CO2 from Light Gas Mixtures using Silicoaluminophosphates Nanoporous Sorbents: Effect of Multiple Step Ion Exchange and Adsorption Mechanism via Computational Studies, Ana G. Arévalo-Hidalgo, Juan A. Santana, Rqiang Fu, Yasuyuki Ishikawa and Arturo J. Hernández-Maldonado, Microporous & Mesoporous Materials, 130 (2010) 142.
  7. Relativistic multireference many-body perturbation theory for open-shell ions with multiple valence shell electrons: the transition rates and lifetimes of the excited levels in chlorinelike Fe X, Yasuyuki Ishikawa, Juan A. Santana, Elmar Traebert, J. Phy. B (Special issue on High Precision Atomic Physics) 43 (2010) 074022.
  8. Relativistic R-matrix close-coupling method based on the effective many-body Hamiltonian: Electron-impact excitation of electric dipole-allowed and spin-forbidden transitions of the S4+ ion, J. A. Santana and Y. Ishikawa, J. Phys. B (Special issue on High Precision Atomic Physics) 43 (2010) 074030.
  9. Electrochemical hydrogen oxidation on Pt(110): A combined direct MD/DFT study, J. A. Santana, J. J.Mateo,Y. Ishikawa, J. Phys. Chem. C 114 (2010) 4995
  10. A density-functional theory study of electrochemical absorption of sulfuric acid anions on Pt(111), Juan A. Santana, Carlos R. Cabrera, Yasuyuki Ishikawa, Phys. Chem. Chem. Phys. 12 (2010) 9526.
  11. In Search of Active Site in Nitrogen-doped Carbon Nanotube Electrodes for Oxygen Reduction Reaction, Chitturi Venkateswara Rao, Carlos R. Cabrera and Yasuyuki Ishikawa, J. Phys. Chem. Letters, 1 (2010) 2622
  12. Interactions between water and carbon monoxide adsorbed on Pt and Pt-Ru alloy surfaces under electrochemical conditions: density-functional theory study, J. A. Santana and Y. Ishikawa, Electrochimica Acta, 56 (2010) 945.
  13. EUV spectra of highly charged Pt ions with several valence-shell electrons: Observation and accurate calculations, E. Traebert, J. Clementson, P. Beiersdorfer, J. A. Santana, and Y. Ishikawa, Physical Review A 82 (2010) 062519.
  14. Synthesis and electrocatalytic oxygen reduction activity of graphene-supported Pt3Co and Pt3Cr alloy nanoparticles, Chitturi Venkateswara Rao, Arava Leela Mohana Reddy, Yasuyuki Ishikawa  and Pulickel M. Ajayan, Carbon 49 (2011) 931
  15. Relativistic R-matrix close-coupling method based on the effective many-body Hamiltonian: electron-impact excitation of the 3s2 1S – 3s3p 1PoJ electric dipole-allowed transition of the Ar6+ ion, J. Santana and Y. Ishikawa, Can. J. Phys. (Proceedings of ASOS10 invited talks), in press (2011).