PHOTOCHEMISTRY AND SPECTROSCOPY OF MONOSUBSTITUTED DERIVATIVES OF TUNGSTEN HEXACARBONYL WHICH EXHIBIT LOW-EFFICIENCY PHOTOREACTIVITIES

The photochemistry and electronic and infrared spectroscopy of W(CO)5X, X = Cl-, Br-, I-, NCO-, and CS, are reported. The lowest energy excited state of the latter compound is metal to ligand charge transfer as shown by magnetic circular dichroism spectroscopy. The lowest excited state of the anions is primarily ligand field. The low photoreactivity (ɸ < 0.1) of all of these compounds is interpreted in terms of excited state bonding properties. The previously proposed classification of low reactivity excited state origins is expanded to include both ligand-field and charge-transfer states. © 1979, American Chemical Society. All rights reserved.