Hydrogen migration in acetonitrile in intense laser fields in competition with two-body Coulomb explosion

Tracing ultrafast hydrogen migration in allene in intense laser fields by triple-ion coincidence momentum imaging

“…[2][3][4][5][6][7] Hydrogen migration, i.e., the migration of hydrogen atoms or protons from one site to another within a molecule, is one of such chemical-bond rearrangement processes. [8][9][10][11][12][13][14][15][16] Since the hydrogen migration processes leading to chemical bond rearrangement may open new reaction pathways that could not be realized from the initial geometry of molecules, investigation of the mechanism of ultrafast hydrogen migration will guide us to develop new schemes of controlling chemical-bond breaking/formation by controlling the motion of protons within a hydrocarbon molecule.…”

Communication: Two stages of ultrafast hydrogen migration in methanol driven by intense laser fields

“…[1][2][3][4] In particular, a so-called hydrogen migration process within a hydrocarbon molecule, accompanying the chemical-bond rearrangement associated with ultrafast motion of hydrogen atom͑s͒ or proton͑s͒ induced by an intense laser field, has become one of the most attractive research themes in these years. [5][6][7][8][9][10][11] The proton motion within a molecule was considered to proceed very rapidly, and it was predicted that this process could occur within the light field. [11][12][13][14] This argument was based on the assumption that those doubly or triply charged species undergo Coulomb explosion immediately after they are formed by the most intense part of the laser pulse and that the hydrogen migration should proceed before the Coulomb explosion.…”

Controlling a Molecule’s Fate

“…As a consequence, the anisotropic angular momentum distribution of channel (1) with peaks along the laser polarization direction indicates, first, that the fragmentation process takes place from an excited ionic state of the ethylene dication formed by ionization of at least one HOMO-2 electron. Second, the strong anisotropy indicates that the fragmentation happens fast as compared to the rotational period of C 2 H 4 2þ [21]. The isotropic angular momentum distribution of channel (2) [and also that of channel (3)], in contrast, suggests that the separation of the two fragments takes longer than the rotational period and happens long after the laser pulse has faded [35,47].…”

“…Hydrocarbons with their intrinsically very fast intramolecular nuclear dynamics of the light hydrogen atoms or protons, which leads to a rich restructuring dynamics, are particularly interesting and have been the object of numerous experimental studies, both using coincidence detection of the molecular fragments [1,[6][7][8]16,17,[21][22][23][24][25] and without coincidence detection [9,10,26,27].…”