MOLECULAR STRUCTURE AND ELECTRONIC PROPERTIES OF DIATRIZOATE, IOXAGLATE CONTRAST COMPOUNDS BY QUANTUM CHEMICAL CALCULATIONS

Iodinated radiographic contrast media for intravascular use are tri-iodinated derivatives of benzoic acid and they all have biological properties that may affect a variety of physiological processes [1]. The optimization of 1,3,5 tri-iodinated benzene, diatrizoate, ioxaglate contrast agent was done in order to calculate the energetic behavior and dipole moment of the title compound in gas phase and water. To support that we will comparing these results with UV-visible and IR excremental data. The total energy for different orbital transitions, energy gap between HOMO and LUMO, electro-negativity, chemical hardness, softness, electrophilicity index and dipole moment have been calculated with cep-4g, cep-31g, cep-121g and B3lyp/lanl2dz levels. The four important molecular orbitals (MO) for the title molecule: the second highest and highest occupied MOs and the lowest and the second lowest unoccupied MOs which were denoted as HOMO-1, HOMO, LUMO and LUMO+1, respectively are the critical parameter in determining molecular electrical transport properties because it is a measure of electron transition. The surfaces of HOMO-1, HOMO, LUMO and LUMO+1 for diatrizoate are given in Figure. 1 to understand the bonding scheme of present compound.