Polarizabilities and energetics of boroxopyrrole homologues studied by ab initio and density functional methods

Molecular geometries, static polarizabilities and energetics have been calculated for the boroxopyrrole (iso-electronic to pyrrole) homologues including boroxopyrrole (B 2 O 2 H 3 N), boroxophosphorylpyrrole (B 2 O 2 H 3 P), boroxoarsenylpyrrole (B 2 O 2 H 3 As) and boroxoantimonylpyrrole (B 2 O 2 H 3 Sb) at the Hartree-Fock by ab initio and Density Functional Theory (DFT) by choosing combined exchange correlation potentials B3LYP and B3PW91. All the calculations utilized the 6-311G basis set for lighter atoms and 3-21G for heavier atoms The influence of substitution with heavy atoms on molecular properties of the homologues was examined theoretically. The calculated results here, show that substitution of the heteroatom with heavy atoms, systematically, increases the individual components of static polarizability, a. This property has been discussed in term of Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) energies. Further, to check the adequacy of the method and the suitability of the basis set, the normal mode frequencies in C 2v symmetry was examined theoretically for B 2 O 2 H 3 N and compared with available experimental data.