Cyanovinylacetylene C5H3N was investigated by threshold photoelectron spectroscopy. The ionization energy (IE) was determined to be 10.04 eV. This value constitutes an upward revision of the earlier value of 9.33 eV. For both stereoisomers (trans and cis) computations predict very similar IEs and spectra. At 11.08 eV and 11.17 eV excited cationic states are observed. For the precursor 3-bromopyridine an IE of 9.34 eV was obtained. The appearance energy AE(0K) (3-bromopyridine, 3-pyridyl(+)) was determined to be 11.71 eV and a bond dissociation energy of the C Br bond in the 3-bromopyridine cation of 229 kJ mol(-1) was derived. (C) 2015 Elsevier B.V. All rights reserved.