Jacqueline Potier

Structure cristalline de ClO2 par spectroscopie de vibration infrarouge et raman

Abstract The infrared (4000–180 cm −1 and Raman (1200–40 cm −1 ) spectra of crystalline chlorine dioxide can be explained from similarities between ClO 2 and SO 2 (space group Aba ( C 17 2v )) and four molecules (site C 2 ) per unit cell. The assignments made were: v 1 ( A 1 912–917 cm −1 , v 1 ( A 2 ) 939–944 cm −1 , v 1 ( A 1 ) 465 cm −1 , v 1 ( A 2 ) 456–459 cm −1 , v 3 ( B 1 and B 2 ) 1052–1121 cm −1 . The presence of four molecules per unit cell is corroborated by analysis of Raman lattice vibrations. Evidence for the isotopic 35 Cl- 37 Cl effect was found in a partial study of liquid ClO 2 . Dimerization is not possible in the solid state, and consequently it is forbidden in the other states.

Raman spectrum and structure of bromine dioxide

The Raman spectrum of bromine dioxide is interpreted as indicating that it has the dimeric structure Br2O4 with a Br–Br bond.