“…The ionization energy of hexacene in the NIST database 6.36 (2) eV and that of naphtho[1,2‐b]triphenylene 7.40 (2) eV give AE a = EN‐IE of 8.00 − 6.36 = 1.64 eV and 8.00 − 7.40 = 0.60 eV, in agreement with the reported AE a values of 1.58 (5) eV and 0.61 (3) eV from half‐wave reduction potentials . Finally, it is suggested that, assuming that thermal decomposition does not take place, the ground state AE a of hexacene and pentacene could be measured from high‐temperature mass spectrometric thermal data as applied to SF 6 and C 7 F 14 …”