Robabeh Mousavi - Department of Physical Chemistry, Faculty of Basic Sciences, Mohaghegh Ardabil University, Iran
Amirnaser Shamkhali - Department of Physical Chemistry, Mohaghegh Ardabil University-Iran
Mohammadreza Zammanlo - Educational Department of Organic Chemistry of Mohaghegh Ardabili University
Rahmat Imani - Department of Mapping, Faculty of Arman Suleh, Ardabil University of Applied Sciences, Iran

With the uncontrolled increase of world population and due to the reduction of energy resources, scientists have thought about using clean and renewable energy such as wind, sun, tide, etc. to use clean and cheap energy with the aim of reducing Environmental pollution, along with increasing the productivity of photovoltaic cells, three organic dyes based on tri-azine were used. The structure of these three dyes was plotted by Gaussian software and optimized by Gaussian program, then in terms of electron excitation. Verticals were studied by DFT and TDDFT quantum methods in gas and liquid phases by SMD method. In this type of pigments, due to the presence of the pigment agent in the structure of molecules, we see the scattering of electron clouds and orbital overlap, which cause more polarization and resonance in them. The effect of polar solvent also intensifies it. As the energy gap decreases by the solvent, charge separation and bond lengths occur in the pigments. According to Homo and Lumo energy forms, λ max wavelength changes, D-CT electron transfer changes, ∆π charge changes and Δμ excitation transfer density changes, three pigment comparisons in gas and solution phases were performed and found:For the first dye, the blue or hypsochromic transfer is not separated, the transitions are n → π * and are localized.For the other two pigments, red or batochromic transfer has taken place, in the pigments, separation has occurred and the transfers are of the type n → π * and are delocalized.

Solar Cell, Electronic excitation, Organic pigments, Load density, Resonance