Sections of the rotational spectrum of g-n-PrCN showing transitions with partially resolved ¹⁴N quadrupole splitting. The upper trace shows the 7, 6−6, 6 a-type R-branch transition with a 1:2 HFS pattern, the lower trace shows the 13, 1, 12−13, 0, 13 b-type Q-branch transition with a 2:1 HFS pattern. Transitions for ν₃₀ = 0, 1, and 2 are shown from left to right in both cases; the vibrational labels are given above the two HFS components, their assignments are indicated below the ν₃₀ = 1 lines.