1. I see DMSO in MW database under Dimethyl sulfoxide. There is also frequency for MMS.
Also a few days ago there was a post on this forum about experimental MMS frequencies
2. Chlorine Dioxide:
Calculated with the spreadsheet of Manual Mallo: Chlorine Dioxide (CDS): 201.059169,25735.573731
Calculated with the spreadsheet of Manual Mallo: Dimethyl Sulfoxide (DMSO): 232.898705,29811.034279
For more details, please check the link: