title: Vibrational interference effects in x-ray emission of a model water dimer: implications for the interpretation of the liquid spectrum.
abstract: We apply the Kramers-Heisenberg formula to a model water dimer to discuss vibrational interference in the x-ray emission spectrum of the donor molecule for which the core-ionized potential energy surface is dissociative but bounded by the accepting molecule. A long core-hole lifetime leads to decay from Zundel-like, fully delocalized vibrational states in the intermediate potential without involvement of a specific dissociated component. Comparison is made to a model with an unbound intermediate state allowing dissociation to infinity which gives a sharp, fully dissociated feature, and a broad molecular peak at long core-hole life time. The implications of the vibrational interference effect on the liquid water spectrum are discussed and it is proposed that this mainly gives rise to an isotope-dependent asymmetrical broadening of the lone pair peak.
authors.affiliation: FYSIKUM, Stockholm University, AlbaNova, S-106 91 Stockholm, Sweden.
authors.forename: M P
authors.initials: MP
authors.lastname: Ljungberg
authors.forename: L G M
authors.initials: LG
authors.lastname: Pettersson
authors.forename: A
authors.initials: A
authors.lastname: Nilsson