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The gas-phase vibrational spectroscopy of cold C 2n N - (n=2-4) anions is investigated in the CC and CN multiple bond stretching region (1700-2250 cm -1 ) by means of infrared photodissociation (IRPD) spectroscopy in a cryogenically cooled ion trap of the corresponding messenger-tagged complexes. The IRPD spectra are assigned to N-terminated linear structures with triplet ground states ( 3 Σ - ) based on a comparison with harmonic vibrational frequencies and intensities from density functional theory computations. In contrast to the polyacetylenic C 2n+1 N - anions, the linear C-C chains investigated here exhibit cumulenic character, which is most pronounced in C 4 N - and decreases with chain length. Additional intense transitions are observed for C 6 N - above 3000 cm -1 and are attributed to overtone and combination bands involving the CC stretching modes, based on anharmonic computations. The influence of a D 2 tag on the vibrational features of C 2n N - anions is shown to be small., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)