Infrared photodissociation spectra and solvation structures of Cu +(H 2O) n ( n = 1–4)

Abstract

Coordination and solvation structures of the Cu +(H 2O) n ions with n = 1–4 are studied by infrared photodissociation spectroscopy and density functional theory calculations. Hydrogen-bonding between H 2O molecules is detected in Cu +(H 2O) 3 and Cu +(H 2O) 4 through a characteristic change in the position and intensity of OH-stretching transitions. The third and fourth waters prefer hydrogen-bonding sites in the second solvation shell rather than direct coordination to Cu +. The infrared spectroscopy verifies that the gas-phase coordination number of Cu + in Cu +(H 2O) n is two and the resulting linearly coordinated structure acts as the core of further solvation processes.