Calculation of ground state term energies ofBH, BH2 and BH3 molecules

In this work, geometric symmetries of BH, BH2 and BH3 molecules were investigated. By the use of symmetry properties and group theory, symmetrized base functions were found and molecular orbitals (MO's) were stated as linear combination of newly found basis functions.For the ground state electron configurations BH, BH2 and BH3 molecules, determinantal wave functions were constituted and their coupling-projection coefficients were calculated. With the help of found expressions, solving Hartree-Fock-Roothaan (HFR) equations, total energies, orbital energies and linear combination coefficients were calculated, obtained results were compared with literature.