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arXiv · 1201.2537

Quantum dynamics of proton migration in H2O dications: formation of H2+ on ultrafast timescales

Manish Garg·Ashwani K. Tiwari·Deepak Mathur
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Abstract

Irradiation of isolated water molecules by few-cycle pulses of intense infrared laser light can give rise to ultrafast rearrangement resulting in formation of the H2+ ion. Such unimolecular reactions occur on the potential energy surface of the H2O2+ dication that is accessed when peak laser intensities in the 1015 W cm-2 range and pulse durations as short as 9-10 fs are used; ion yields of ~1.5% are measured. We also study such reactions by means of time-dependent wavepacket dynamics on an ab initio potential energy surface of the dication and show that a proton, generated from O-H bond rupture, migrates towards the H-atom, and forms vibrationally-excited H2+ in a well-defined spatial zone.

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Manish Garg, Ashwani K. Tiwari, Deepak Mathur. 2012-01-12. Quantum dynamics of proton migration in H2O dications: formation of H2+ on ultrafast timescales. https://doi.org/10.1063/1.3676086

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