A CORRELATION BETWEEN VOLATILITY AND MOLECULAR STRUCTURE: SPECTROSCOPIC ESTIMATION OF THE TEMPERATURE FOR ONSET OF SUBLIMATION IN METAL P-DIKETONATES

摘要

A theoretical model, based on the conservation of energy has been developed, in terms of parameters such as vibralional-rotational and electronic energy of the molecule, modified based on experimental observations, and the temperature for the onset of sublimation was calculated for the complexes tris(2,4-pentadionato)aluminium(Ⅲ) [Al(pd)_3], tetrakis(2,4-pentadionato)zirconium(Ⅳ) [Zr(pd)_4], and bisaquo bis(2,4-pentadionato)cobalt(Ⅱ) [Co(pd)_2.2H_2O] using IR, Raman, and Ultraviolet-visible spectroscopic data at room temperature. The calculated values of temperature for the onset of sublimation of the complexes Al(pd)_3, Zr(pd)_4, and Co(pd)_2.2HK_2O are 113℃, 143℃, and 130℃ respectively. The calculated values are in close agreement with experimental values obtained from TGA/DTA analysis. This correlation could lead to the rational pathways to design precursor molecule for MOCVD and to test the applicability of variety of organometallic compounds in MOCVD process as well.