Photoinduced water splitting in pyridine water clusters

Ab initio calculations predict that pyridine (Py) can act as a photo-catalyst to split water by the absorption of a UV photon following the reaction Py-H 2 O + hν → PyH&z.rad; + OH&z.rad;. To test this prediction, we performed two types of experiments: in the first, we characterize the electronic spectroscopy of the PyH&z.rad; radical in the gas phase. In the second, we evidence the reaction through the UV excitation of molecular Py-(H 2 O) n clusters obtained in a supersonic expansion and monitoring the PyH&z.rad; reaction product. The results show unambiguously that PyH&z.rad; is produced, and thus that water is split using pyridine as a photo-catalyst. Photon induced water splitting in pyridine-(H 2 O) n clusters observed through the detection of the pyridinyl radical.