^a Frequencies and spectroscopic parameters have been provided by Cazzoli & Puzzarini (2006) and Müller et al. (2009) and by the Jet Propulsion Laboratory molecular database Pickett et al. (1998) for CH₃CN, while they were provided by Müller et al. (2009) and retrieved from the Cologne Database for Molecular Spectroscopy (Müller et al. 2005) for CH₂DCN.^b The errors in brackets are the Gaussian fit uncertainties.^c Blended with unidentified line (see Fig. C.1 and Fig. C.2) and thus excluded from the further analysis.^d Excluded from further analysis since the line peak is below the detection threshold (S/N > 3σ see Sec. 2.2).^e Conservatively excluded from the analysis since the line profiles are broad (composed of different transitions close in frequency, see Fig. C.1 and C.2).^f Blended with CH₃OH 18_3,16–18₂,₁₇ A, 257.4021 GHz, E_up= 447 K.^g These transitions are only detected by the NOEMA/SOLIS observations. The low spectral resolution (6–7 km s⁻¹) does not allow us to safely estimate the line width. A Gaussian fit is not performed given the unresolved line profiles. We note that all the expected CH₂DCN transitions are detected in the NOEMA/SOLIS dataset, but we consider conservatively only these two lines which are not contaminated by other molecular species.^h Blended with CH₃CHO 11_0,11−10_0,10 A, 208.2670 GHz, E_up= 60 K.ⁱ These transitions have the highest upper level energy of all the detected transitions, while others with similar intensities and lower energies are not detected. To be conservative we decided to exclude the line from the analysis.^j Blended with HCOOCH₃ 19_3,17−18_3,16 A, 225.6187 GHz, E_up= 117 K.^k Blended with H₂CO 3_1,2−2_1,1, 225.6978 GHz, E_up= 33 K.¹ Blended with HCOOCH₃ 20_2,19–19_2,18 E, 226.7131 GHz, E_up=120 K.^m Blended with CH₂DOH 11_2,9–11_1,10 o1, 242.0336 GHz, E_up= 177 K.ⁿ Blended with C³³S 5–4, 242.9136 GHz, E_up= 35 K.