Identifying the Multielectron Effect on Chemical Bond Rearrangement of CH 3 Cl Molecules in Strong Laser Fields.

Strong field double ionization that triggers the chemical bond rearrangement of CH ₃ Cl is investigated by impulsive control of the alignment of molecules. The alignment and laser intensity dependent H ₂ ⁺ and H ₃ ⁺ yields in linearly polarized femtosecond laser have been measured, and the obtained data show that the maximum signal of H ₂ ⁺ appears at the laser polarization parallel to the C-Cl axis of molecules and H ₃ ⁺ species are more likely to eject at the laser polarization parallel to the C-Cl axis at low laser intensity while the H ₃ ⁺ signal peaks at laser polarization perpendicular to the C-Cl axis at high laser intensity. The measurements indicate that electrons from HOMO - 1 and HOMO - 2 orbitals have been ionized for the generation of bond rearrangement at different laser intensity. Our results demonstrate the importance of multielectron effects and also provide an effective control method in the process of chemical bond rearrangement of the molecules in strong laser fields.