Control theory of nonadiabatic electron dynamics in general pi-conjugated systems driven by polarized laser pulses

2016 Fiscal Year Final Research Report

• Project/Area Number: 26810002
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Physical chemistry
• Research Institution: Tohoku University
• Principal Investigator: Kanno Manabu 東北大学, 理学研究科, 助教 (30598090)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 超短レーザーパルス / 偏光 / π電子系 / 非断熱ダイナミクス / 無輻射遷移 / 多光子イオン化 / 光解離 / 動力学計算

Outline of Final Research Achievements

The control theory of laser-induced ring currents nonadiabatically coupled with skeletal vibration in aromatic molecules has been extended to general pi-conjugated systems. Contrary to a recent semiclassical study that suggested the participation of several optically dark states in ultrafast internal conversion of pyrazine, quantum dynamical calculations demonstrated that the nonadiabatic transition to the lowest dark state occurs directly after optical excitation, and that the transition rate is much faster than previously estimated in experiments. The present theory was also applied to C60 and its derivatives. The decisive factor of ellipticity-dependent multiphoton excitation probability in spherical systems such as C60 is transition moment magnitudes. Polyhydroxy fullerenes heated by near-infrared lasers undergo H2O and CO evaporations. The cage structure is then broken into a graphene-like flake form, leading to coalescence into larger nanocarbons such as carbon nanotubes.

Free Research Field

化学