Text this: High resolution FTIR spectroscopy of sulfur dioxide in the 1550-1950 cm−1 region: First analysis of the ν1+ν2/ν2+ν3 bands of 32S16O18O and experimental line intensities of ro-vibrational transitions in the ν1+ν2/ν2+ν3 bands of 32S16O2, 34S16O2, 32S18O2 and 32S16O18O