Abstract
Rotational mechanisms of a chiral molecular motor driven by femtosecond laser pulses were investigated on the basis of results of a quantum control simulation. A chiral molecule, (R)-2-methyl-cyclopenta-2,4-dienecarboaldehyde, was treated as a molecular motor within a one-dimensional model. It was assumed that the motor is fixed on a surface and driven in the low temperature limit. Electric fields of femtosecond laser pulses driving both regular rotation of the molecular motor with a plus angular momentum and reverse rotation with a minus one were designed by using a global control method. The mechanism of the regular rotation is similar to that obtained by a conventional pump-dump pulse method: the direction of rotation is the same as that of the initial wave packet propagation on the potential surface of the first singlet (n π*) excited state S1. A new control mechanism has been proposed for the reverse rotation that cannot be driven by a simple pump-dump pulse method. In this mechanism, a coherent Stokes pulse creates a wave packet localized on the ground state potential surface in the right hand side. The wave packet has a negative angular momentum to drive reverse rotation at an early time.
Original language | English |
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Pages (from-to) | 272-278 |
Number of pages | 7 |
Journal | Chemical Physics |
Volume | 347 |
Issue number | 1-3 |
DOIs | |
Publication status | Published - 2008 May 23 |
Keywords
- Femtosecond dynamics
- Molecular chirality
- Molecular motor
- Quantum control
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry