Oxygen-18 isotope effects in the electronic spectrum of UO2F2

The substitution of 18O for 16O in UO2F2 produces changes in the electronic spectrum. Both positions and intensities of peaks change. To clarify these changes, the well-known narrowing effect of lowered temperature on the uranyl spectrum was used. The spectrum of UO2F2 in methanol at 203 K supports the conclusions based on the room-temperature spectrum. Experimental details are presented, and results are discussed. (U.K.)