ABSTRACT
The various isomers of the XOOI, XOOOI, X=H, CH3 families are investigated using the MP2 methodology combined with two types of basis sets, the 6-311G basis set for all atoms involved and the 6-311G basis set for C, H and O combined with the LANL2DZ ECP procedure for I, augmented with extra polarization functions. The results indicate the improvement accomplished in the quantum treatment of I when additional polarization functions and relativistic corrections are taken into account. In addition, the variations of the I-O bond distances in all types of calculations reveal the differences in the nature of I-O bonding that occur in the various isomeric species. The hypervalent character of I in some isomeric forms is found to have a profound effect in the relative stability order among the members of each family.
