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Abstract
In this work an attempt has been made to rationalize the effect of the X substituent on the structures and stabilities of the substituted methy1 anions ( CH2X- ), cations ( CH2X+ ), and radicals ( CH2X ), as X varies along a period or along a group .The substituents were chosen from extends from K to I ). Substituents from the first ( x = Li – F ) and second ( X= Na Cl ) rows are also included for comparison.
This thesis consists of three chapters:
1- shows the importance of the compounds under investigation and reviews briefly what has been done on these species. At the end of this chapter, the aim of the present work is summarized.
2- We have summarized the computational methods employed in this work. Ab initio calculations were carried out using Gaussian 90 and 92 series of programs implemented on convex and cray computers.
3- The results obtained are discussed and can be summarized .