Ultrafast imaging of multielectronic dissociative ionization of CO₂in an intense laser field

Abstract

Momentum vectors of fragment ions produced by the Coulomb explosion of CO2z+ (z = 3–6) in an intense laser field (∼50 fs, 1 × 1015 W cm−2) are determined by the triple coincidence imaging technique. The molecular structure from symmetric and asymmetric explosion channels is reconstructed from the measured momentum vectors. The channel-dependent mean C–O bond length of ⟨r⟩ = 2.14–3.89 Å and the O–C–O bend angle of ⟨θ⟩ = 170–175° confirm substantial deformation of the molecular skeleton during the laser-molecule interaction. The channel-dependent bond length data are qualitatively described using a classical enhanced ionization model. The kinetic energy spectra reveal interesting structure which is attributed to the existence of excited states in the fragment ions.

Dissociative double ionization of CO2induced by intense femtosecond laser pulses

“…It can be seen that abundant CO 2 + , CO + , CO 2 2+ , O + , C + , and C 2+ ions are produced during the interaction of CO 2 with intense femtosecond laser pulses. These observations are consistent with previous papers [15][16][17][18][19][20]. Because of the initial velocity of the CO 2 supersonic molecular beam, the centers of the above-mentioned ions in the detector (see the black line in the bottom panel of Fig.…”

Electron ionization of CO2

“…Our data shows that dissociation of CO 2 3+ to form an ion triple, C + + O + + O + , is the most abundant trication dissociation channel at all ionizing energies investigated in this study. Indeed, the propensity of symmetric charge separation among the ion fragments formed upon dissociative multiple ionization of CO 2 has been observed previously, in studies using intense laser pulses [28] and involving collisions with high energy ions [27,45].…”

“…The dissociative ionization of CO 2 has been the subject of a number of investigations employing a variety of techniques: electron-ionization mass spectrometry [4][5][6][7][8][9][10][11][12][13][14][15][16][17], photoionization mass spectrometry [18][19][20][21][22][23][24][25], collisions with positrons [26], collisions with high translational energy ions [27], ultrafast laser pulses [28] and coincidence techniques [19][20][21][23][24][25]27,29,28]. Concentrating on the previous cross determinations for electron ionization of CO 2 , the total ionization cross section has been measured from threshold to 100 eV by Asundi et al [4] and from threshold to 1000 eV by Rapp and Englander-Golden [5].…”

Communication: Determining the structure of the N2Ar van der Waals complex with laser-based channel-selected Coulomb explosion

“…[22][23][24][25][26][27][28] The results have demonstrated that the nuclear motion can be frozen for molecules in the process of multiple ionization by using ultrashort laser pulses. 14,25,28 Thus, the reconstructed structure of the molecular ion before explosion can represent the structure of the neutral precursor molecules when such ultrashort laser pulses are applied.…”