Metal phthalocyanines (MPcs) have received a great attention due to their interesting electrical, optical and structural properties with high chemical and thermal stabilities [1], followed by numerous applications such as gas sensors, low area displays, solar cells [2–4], organic field effect transistors [5,6]. Recently, many research groups have systematically studied the Pc-based molecular systems, in which perylene have been used as electron acceptors. Other kinds of important electron acceptors and electron transporting materials are perylene derivatives with planar structures. Generally, phthalocyanines and perylene tetracarboxylic derivatives are known to be insoluble in most solvents except for sulfuric acid. It is one of the limiting factors for their applications. However, this paper for the solution processable ZnPc/Bis-3-Pentyl-PTCBI composite thin films used formic acid (FA) of 99 % concentration. For the preparation of a donor-acceptor molecule, N, N'-bis (3-pentyl) perilen-3,4,9,10-bis (dicarboximid) (97%) (Bis-3-Pentyl-PTCBI) and zinc phthalocyanine (ZnPc) powder (98% purity) were purchased from Sigma Aldrich. The prepared solution was used for the deposition of composite thin films on glass substrates by the drop casting and spin coating methods. A variety of techniques was employed to assess the structure of composite thin films. The structure of the films was analyzed by X-ray Bruker D8 advanced diffractometer (using CuKα radiation with λ=1.5406 Å). The phase analysis of the films was examined using Raman microspectroscopy with Ar+ laser (514 nm) as an excitation source, integrated with an optical microscope (Renishaw in via). b The measurements are made on pure and iodine doped ZnPc, undoped and iodine doped ZnPc/Bis-3-Pentyl-PTCBI composite thin films deposited on glass substrates from chemical solution. The X-ray diffractograms of the all thin films deposited from FA solution exhibit polycrystalline structure. The XRD curve for the undoped and iodine doped ZnPc/Bis-3-Pentyl-PTCBI composite thin films present Bis-3-Pentyl-PTCBI and α-ZnPc phases, respectively. Raman analysis revealed that the Zn-nitrogen vibration is observed at 225 cm-1 and the vibration due to in-phase motion of isoindole groups is seen at 157 cm-1 for undoped ZnPc. The breathing vibration of the 16-membered inner ring with strong relative intensity is observed at 673 cm-1. Raman bands observed at 744 cm-1 and 827 cm-1 could be associated with macrocycle deformations. The most intense Raman band is observed at 1501 cm-1. This band is assigned to the stretching vibration of the Cβ-Cβ bond in the pyrrole group, and is a totally symmetric vibration. The band at 1334 cm-1 is assigned to the Cα-Cβ stretching vibration of the pyrrole group. Breathing stretching vibration of pyrrole groups is seen at 1140 cm-1 and the corresponding breathing vibration of benzene group is observed at 947 cm-1. In the case of ZnPc/Bis-3-Pentyl-PTCBI composite thin films the formate ion, HCOO-, displays a lower intensity vibration band at 1031 cm-1. So, the XRD and Raman analysis allow us to conclude that the formate ion, HCOO- interact with Zn and form Zn(HCOOH)Pc formate supramolecular complexes. Also, the absorption spectra of all films were investigated and will be discussed. The spectra have a high and broad absorption, and show the effect of mixing in the electronic spectra of both Bis-3-Pentyl-PTCBI and ZnPc components.