Photodissociation spectrum and structure of Au4+·H2O clusters

- New laser-desorption mass spectrometer for spectroscopy of size-selected cluster ions.
- Optical photodissociation spectra of Au4+ and Au4+·H2O clusters are analyzed.
- Structures are derived from global optimization and long-range corrected DFT calculations.
- H2O adds to the most stable Au4+ rhomboid (D2h) with an AuO bond of 1.15 eV.
- The partially covalent AuO bond in Au4+·H2O is much weaker than in Au+·H2O.