“…(15) and (16) with the experimental results. For χ = 1, i.e., using the simple diatomic mass, one obtains, for the infrared lines of the 29 Si and 30 Si components of VH 4 , IS of 0.99 and 1.92 cm −1 , respectively, and for those of VD 4 , IS of 1.39 and 2.70 cm −1 , respectively. These values are slightly larger than the observed ISs in Figs.…”