Abstract
The pure rotational Raman spectra of 16O2, 16O18O and 18O2 have been recorded and analysed, the latter two for the first time. The following rotational constants and bond lengths were determined: 16O2 : B0= 1.437 685 ± 0.000 05 cm–1; 106D0= 4.61 ± 0.09 cm–1; Be= 1.445 8 ± 0.000 3 cm–1; r0= 1.210 85 ± 0.000 03 Å; re= 1.207 4 ± 0.000 2 Å. 16O18O : B0= 1.357 81 ± 0.000 08 cm–1; 106D0= 4.7 ± 0.2; Be= 1.365 3 ± 0.000 3 cm–1; r0= 1.210 77 ± 0.000 06 Å; re= 1.2075 ± 0.000 2 Å. 18O2 : B0= 1.278 03 ± 0.000 05 cm–1; 106D0= 3.84 ± 0.05; Be= 1.284 7 ± 0.000 3 cm–1; r0= 1.210 64 ± 0.000 04 Å; re= 1.207 5 ± 0.000 1 Å. These r0 and re values agree with the bond lengths determined by microwave spectroscopy to within one standard deviation of error.