Selective Bond Dissociation and Rearrangement with Optimally Tailored, Strong-Field Laser Pulses

Abstract

We used strong-field laser pulses that were tailored with closed-loop optimal control to govern specified chemical dissociation and reactivity channels in a series of organic molecules. Selective cleavage and rearrangement of chemical bonds having dissociation energies up to approximately 100 kilocalories per mole (about 4 electron volts) are reported for polyatomic molecules, including (CH 3 ) 2 CO (acetone), CH 3 COCF 3 (trifluoroacetone), and C 6 H 5 COCH 3 (acetophenone). Control over the formation of CH 3 CO from (CH 3 ) 2 CO, CF 3 (or CH 3 ) from CH 3 COCF 3 , and C 6 H 5 CH 3 (toluene) from C 6 H 5 COCH 3 was observed with high selectivity. Strong-field control appears to have generic applicability for manipulating molecular reactivity because the tailored intense laser fields (about 10 13 watts per square centimeter) can dynamically Stark shift many excited states into resonance, and consequently, the method is not confined by resonant spectral restrictions found in the perturbative (weak-field) regime.