The pure rotational Raman spectrum of 19F2 has been recorded photographically with a reciprocal linear dispersion of 1.4 cm–1 mm–1 and analysed to yield; B0= 0.883 31 ± 0.000 04 cm–1; 106D0= 3.48 ± 0.06 cm–1; r0= 1.417 44 ± 0.000 06 Å. Assuming from earlier work, B1= 0.872 ± 0.002 cm–1, the following equilibrium constants were obtained; Be= 0.889 ± 0.001 cm–1; re= 1.4131 ± 0.000 8 Å. These are the most precise values yet reported for B0, D0 and r0, re of 19F2. The experimentally determined D0 value is in good agreement with the value calculated from B0 and ω0.