Polymeric products, which are formed by reaction of the dications of (7E,7’Z)-diphenyl-7,7’-diapocarotene (I) generated by electrochemical oxidation in dichloromethane with the neutral carotenoid, are adsorbed on various electrode surfaces. An apparent average molar mass of 5400 g/(mol electrons) was calculated from simultaneous electrochemical quartz crystal microbalance (EQCM) measurements, and the green, fiber-like structure observed by optical microscopy confirms the formation of polymers. X-ray microanalysis of the surface composed of an uneven, layered structure indicates that electrolyte counter anions PF6- are associated with the deposited material. Cathodic stripping voltammetry indicates that the firm thickness ranges from 0.16 to 0.84 mu m as the charge increases from 10.0 to 51.1 mu C. Cation radicals of I show no adsorption behavior nor do the dications of carotenoids terminally substituted with one cyclohexene ring (V) or containing a triple bond at C15 (IV). Apparently a diphenyl-substituted carotenoid containing only double bonds in the backbone is required to observe this unusual behavior.