The infrared spectra of (SF6)-S-32, (SF6)-S-33 and (SF6)-S-34 dimers were studied in argon and nitrogen matrices. The spectra of SF6 dimers of like and unlike isotopomers were also calculated taking into account the resonance dipole-dipole and dipole-induced dipole interactions between two triply degenerate oscillators. Two absorption bands with site structure are observed for ((SF6)-S-32)(2), ((SF6)-S-33)(2) and ((SF6)-S-34)(2) in argon, the nu(X,Y) band is blue shifted and the nu(Z) band is red shifted from the nu(3) SF6 band in accordance with calculated spectra. Three and two components of the predicted quadruplets are identified for (SF6)-S-32-(SF6)-S-34, (SF6)-S-32-(SF6)-S-33, respectively, In the spectra of (SF6)., in nitrogen matrices the splitting of nu(X,Y) component of the resonance doublet was observed. (C) 2002 Published by Elsevier Science B.V.