As described in the Introduction, the data tables for each molecule consist of a table of derived molecular constants followed by the spectral line table. These are ordered alphabetically by the atomic symbols.
The molecular constants are presented for each isotopic species in the order: rotational constants, hyperfine structure constants, electric and magnetic dipole moments, reduced mass, and when appropriate, additional references which were not utilized in the tabulation.
The spectral line tables were organized first by isotopic species. For each species the transition frequencies are listed by increasing J′ and by increasing υ for each J′. The hyperfine structure for each rotational transition is ordered by increasing transition frequency.