The article determines the technological conditions of growing the films of solid solution (GaAs)1-x-y(Ge2)x(ZnSe)y on GaAs substrates by the method of liquid phase epitaxy from the tin melt-solution. The grown epitaxial films had the thickness of ~ 10 μm, n -type conductivity with specific resistances of ~ 0.1 Ωˑcm and the current carrier concentration of 5.1ˑ1017 cm-3. Spectral photosensitivity of n-GaAs – p-(GaAs)0.69(Ge2)0.17(ZnSe)0.14heterostructureshave been studied and two distinct peaks corresponding to Ge nanocrystals with GaAs molecule compounds and ZnSe quantum dots have been detected. It is shown that the photosensitivity spectrum of the studied solid solution has six Gaussian components which correspond to the pair atoms of Ge2 and compounds AsGe, GaGe, GeSe, AsZn, GaSe and ZnSe. The spatial configurations of tetrahedral bonds within nanoclusters formed by Ge and ZnSe impurities based on a GaAs unit cell are presented. It is also determined that the nanoclusters in the solid solution (GaAs)1-x(Ge2)x consist of three As atoms, two Ge atoms and three Ga atoms. Since the unit cell of the lattice with the diamond-like structure consists of eight atoms, the linear dimensions of the nanocluster are 5.6, 5.6, 5.6 A. In the nanocluster in the solid solution (GaAs)1-x-y(Ge2)x(ZnSe)y formed by the GaAs molecule, ZnSe and the Ge2 pair atoms contains 14 atoms: five As atoms, two Ge atoms, one Se atom, one Zn atom, and five Ga atoms. So the As and Ga atoms are bound through the Ge, Zn, and Se atoms, and therefore the linear dimensions of the nanoclusters become 5.6; 5.6; 10 A. Thus, the matrix lattice consists of GaAs molecules and twin Ge atoms, and ZnSe molecules are located on their surface defective regions. Since zinc selenide molecules and germanium selenide compounds form three acceptor levels in the GaAs valence band, and the ZnSe lattice parameter is slightly larger than the matrix lattice, at ZnSe locations, the lattice microdistortions are observed and they have an increased potential which promotes the formation of ZnSe nanocrystals.