Vibrational frequencies and structural determinations of 1,4-thioxane

We present a detailed analysis of the structure and infrared spectra of 1,4-thioxane. The vibrational frequencies of the 1,4-thioxane molecule were analyzed using standard quantum chemical techniques. Frequencies were calculated at the MP2 and DFT levels of theory using the standard 6-31G* basis set. The structural transformation of the chemical agent bis (2-chloroethyl) sulfide (HD, mustard gas) and the related symmetry to a previously study compound((4)) makes the symmetry of the 1,4-thioxane molecule an interesting candidate for study. The molecule exists normally in a C-s configuration similar to the chair form of cyclohexane. High-energy forms of 1,4-thioxane with C-1 and C-2 symmetry also exist. (C) 2001 Elsevier Science B.V. All rights reserved.