Masahiko Hada

Title : 51V-NMR chemical shifts and analyses of vanadium complex catalysts: A Cooperation of QC calculation and MLR analysis

Abstract:

In recent studies, Nomura and his coworkers found a good relationship between the catalytic activity and the vanadium chemical shift (51V-NMR) for the (imido) vanadium complex in ethylene polymerization. They deduced that the high catalytic reactivity originates from stabilization of the active site by electron-donating substituents. The trend of observed 51V-NMR chemical shifts was well reproduced by the quantum-chemical calculations (LC-BLYP/cc-pVTZ). Calculated 51V NMR chemical shifts were analyzed by the multiple linear regression analysis (MLRA) method with a series of calculated molecular properties. We obtained a reasonable correlation (R2=0.95) between 51V-NMR chemical shifts and natural charge (Q), HOMO-LUMO energy gap (Δε), and Wiberg bond index of V?N bond (ω)

Biography:

Masahiko Hada studied Quantum Chemistry (QC) in Kyoto University. Recently he has his interests centered around accurate QC calculations including the electron-correlation and the relativistic effects, and computational approaches for analyses of chemical reactions, spectroscopies and molecular properties. Recently his expertise is extended to 2c-relativistic quantum-chemical theories and its applications to NMR, electronic excited states and spectroscopies (UV, CD, MCD, CPL), and chemical reactions on metal and metal-oxide surfaces, and chemical reaction mechanisms of enzyme containing transition metals.