This isomeric ratio dependence with temperature cannot be fully explained with the currently proposed gas-phase formation and destruction pathways. These detections confirm that the H2CN/H2NC ratio is ≳2 for sources with Tkin>70K, larger than the ∼1 ratios previously found in colder cores (Tkin∼10K). We derived molecular abundances with respect to H2 of (6.8☑.3)×10−11 for H2CN and of (3.1☐.7)×10−11 for H2NC, and a H2CN/H2NC abundance ratio of 2.2☐.5. We have detected multiple hyperfine components of the NKaKc=101−000 and 202−101 transitions. In this work, we present the first detection of H2CN and H2NC towards a warm galactic source, the G+0.693-0.027 molecular cloud (with Tkin>70K), using IRAM 30m observations. These detections have shown that the H2CN/H2NC isomeric ratio, likewise the HCN/HNC ratio, might increase with the kinetic temperature (Tkin), but the shortage of them in warm sources still prevents us to confirm this hypothesis and shed light about their chemistry. The H2NC radical is the high-energy metastable isomer of H2CN radical, which has been recently detected for the first time in the interstellar medium towards a handful of cold galactic sources, besides a warm galaxy in front of the PKS 1830-211 quasar. The spectroscopic information for the observed transitions is given in Table A1 of Appendix A. The transitions shown are only those with peak intensities of □ ∗ A > 0.41 mK, which corresponds to □/3 value (where □ is the rms of the spectra). ![]() Magenta vertical lines indicate those transitions selected to perform the AUTOFIT. Black histogram and grey-shaded areas indicate the observed spectrum, while the red and blue lines represent the best LTE fit obtained for H2NC, and the emission of all the species already identified in the cloud (whose names are indicated by the blue labels), respectively. H2NC hyperfine lines observed towards G+0.693, corresponding to the 101 − 000 rotational transition (upper panel) and the 202 − 101 rotational transition (lower panel).
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