HCl H+ signal near agust,heima,...januar09/V8_f3d2(alignment) vhw.pxp

H+ signal

A possible explanation for the H+ signal in (2+n)REMPI for HCl: A transition to a repulsive valence state (t.d. A 1 Pi), followed by direct dissociation to H + Cl, During the dissociation process a resonance excitation of "the dissociating molecule, H--Cl" close to the atom resonance line ( cm-1) occurs followed by ionization, i.e. : 1) HCl + 2hv -> HCl*(A) 2) HCl*(A) -> H--Cl -> H + Cl 3) H--Cl + 2hv -> H*--Cl 4) H*--Cl + hv -> H+ process (3) occurs over a wavenumber range ( cm-1) since it corresponds to transitions between molecular surfaces with different H--Cl distances. It is well known effect that atomic lines broadens due to pressure effects (“pressure broadening”) which is believed to be due to effects of the neighbour species attach to the atom. In our case (i. e H--Cl), the Cl atom is attached to the H atom as it absorbs.