We note that CoO(111) exhibits metallic character and interpret the appearance of these new signals based on studies investigating the behavior of dimethylamine on Pt(111). Dimethylamine has been found to dehydrogenate partially above 300 K to form methylaminocarbyne (MAC, CNHCH3). At 400 K, MAC further dehydrogenates leading to the formation of several different species, including methyl isocyanide (MISO, CNCH3) which exhibits a very characteristic (C≡N) vibration at around 2200 cm -1 . Other proposed surface species exhibit C=N double bonds, e.g. the intermediate formimidine (CHNMe) with (C=N) signals arising around 1600 cm -1 . Based on this information and our observations, we suggest that TDMAH initially reacts with the CoO(111) surface via a Lewis acid-base reaction. However, the -NMe2 ligand is not stable on CoO(111) and immediately undergoes dehydrogenation at 400 K. The hydrogen which is split off then leads to the formation of surface OH groups (giving rise to the formation of the (OH) band at 3676 cm -1 ). The partial decomposition products of the ligand species with C=N double and C≡N triple bonds give rise to the additional bands observed around 2200 and 1600 cm -1 . In particular, we assign the band at 2188 cm -1 to MISO binding to surface Co ions. The broad band between 1630 and 1540 cm -1 probably originates from several different species with C=N double bonds, similar to the findings on Pt(111). We note that we do not observe the characteristic (NH) vibration for MAC at around 3400 cm -1 . This suggests that at 400 K either no or only a very small amount of MAC is formed on CoO(111). Similar to the experiment on CoO(100), we tentatively assign the band at 910 cm -1 to dehydrogenated ligands binding to surface Co ions. The ratio between the different dehydrogenated species changes over the course of the nucleation experiment as reflected by the changing ratio of the corresponding integrated peak areas. At the very beginning, the surface predominantly shows MISO species. With further exposure to TDMAH, more dehydrogenated species are formed, and the ratio gradually shifts towards species with C=N double bonds. Finally, the total amount of dehydrogenated species decreases again. Most notably, all MISO species are gradually lost, while some of the C=N double bond species remain on the surface even at saturation. Simultaneously, the previously formed OH groups on the surface are consumed again. The gradual shift of the (OH) band to lower wavenumbers indicates a change in the interaction with other surface species. Finally, all surface OH is consumed, including the defect OH that was present on the surface after preparation (giving rise to a small positive band at 3676 cm -1 ).