Astrofizik alandaki moleküllerin termokimyasal ve spektroskopik özellikleri

The properties of atom and molecules be obtained from atom-molecule or molecule- molecule collisions or from spectroscopic and thermodynamic analysis of ro-vibrational and translational motion of components of molecule. There have been many spectro- scopic analysis of Astrophysical molecules that observed every recently in parallel to the development of technology of Orion, Herschel telescopes etc . With these telescopes very recently many molecules from diatom to poly-atomic molecules was observed and investigated as a spectroscopic analysis. The outputs form all these spectroscopic analysis are consist of many quantum e¤ects like tunneling and zero point energies which are not possible to calculate by using the classical physics. That is why, it is important to implement quantum mechanical methods to atom-molecule or molecule- molecule interaction to calculate quantum mechanical quantities. Depending of the size of molecule (number of molecule) it is important to implement accurate or ap- proximate quantum methods to the system like Hartree fock (HF), Density Function Theory (DFT) or Con…guration Interaction (CI) and so on. Some of molecules which are important in Astrophysics interest, would be studied in this theses are C2H5, C2H6, NO3, CH3OCH2OO. Depending on the molecule quantum mechanical HF, DFT , CI, etc. theories will be implemented and thermodynamic quantities from contribution of transition, electronic motion, and ro-vibration motion have been calculated.