In order to search for materials with improved semiconductor properties, thin films of GaInP have been fabricated on the GaP surface (the molecular beam epitaxy and ion implantation procedures were used). These films were investigated by the Auger electron spectroscopy, ultraviolet photoelectron and light absorption ones. The energy and angle dependences of the secondary-electron-emission coefficient (SEEC) were obtained as well. An analysis of the experimental data allowed for the first time to determine the main energy-band and emission parameters of the Ga0.6In0.4P/GaP(111) nanofilm. The energy-gap width was found to be 1.85 eV, which was significantly less than that of the substrate GaP, and thus, the maximum value σmax of the SEEC and the quantum yield K of photoelectrons (at hν = 10.8 eV) values of the Ga0.6In0.4P/GaP system decreased slightly relative to the pure GaP.