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arXiv · 1307.7552

Bond-selective fragmentation of water molecules with intense, ultrafast, carrier envelope phase stabilized laser pulses

D. Mathur·K. Dota·J. A. Dharmadhikari·A. K. Dharmadhikari
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Abstract

Carrier envelope phase (CEP) stabilized pulses of intense 800 nm light of 5 fs duration are used to probe the dissociation dynamics of dications of isotopically-substituted water, HOD. HOD$^{2+}$ dissociates into either H$^+$ + OD$^+$ or D$^+$ + OH$^+$. The branching ratio for these two channels is CEP-dependent; the OD$^+$/OH$^+$ ratio (relative to that measured with CEP-unstabilized pulses) varies from 150% to over 300% at different CEP values, opening prospects of isotope-dependent control over molecular bond breakage. The kinetic energy released as HOD$^{2+}$ Coulomb explodes is also CEP-dependent. Formidable theoretical challenges are identified for proper insights into the overall dynamics which involve non-adiabatic field ionization from HOD to HOD$^+$ and, thence, to HOD$^{2+}$ via electron rescattering.

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D. Mathur, K. Dota, J. A. Dharmadhikari, A. K. Dharmadhikari. 2013-07-29. Bond-selective fragmentation of water molecules with intense, ultrafast, carrier envelope phase stabilized laser pulses. https://arxiv.org/abs/1307.7552

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