A CALCULATION OF THE H₂O₂ MOLECULE BY THE LCAO–MO–SCF METHOD

Abstract

The electronic structure of the hydrogen peroxide lnolecule i11 three differe~~t configurations, namely the cis, the trans, and the non-planar or skew forms, were calculated according t o the LCAO-MO-SCF approxin~ation. All the electrons were considered except those of the K-shell of the osygerl atoms. The orbitals of these atonls are essentially of the sp3 hybrid type. It was shown that the skew form of the molecule with an azimuthal angle % of about 120" is the most stable, due mainly to conjugation of the a5 and 0 6 orbitals of the oxygen atoms with the other n~olecular orbitals. On the contrary, in the cis and trans forms these two orbitals are non-bonding. Because of the approximate nature of the treatment, especially as regards the screening effect of the I<-electrons, the calculated orbital energies are definitely too large. However, the heights foulld for the cis and the trans barriers are in a reasonable mutual ratio. N~rrnerical values were also obtained for the ionization potentials and the dipole moment of the skew model; the latter result, 2.05 D, agrees well with the experimental data.

Photoinduced chirality of hydrogen peroxide molecules

“…When we select between left-or right-handed frame, a choice of the direction of the vector n O from one atom to another allows us then to assign a definite sign to the torsional angle ∠HOOH. An equilibrium value of the torsional angle in the gas phase in accordance with theoretical calculations and experimental data is θ ≃ ±120 • [10][11][12][13], where positive sign corresponds to the shown in Fig. 1a so-called d-state (right-handed enantiomer) and negative-to the l-state (left-handed enantiomer).…”

Studies on hydrogen–oxygen systems in the electrical discharge. IV. Spectroscopic identification of the matrix-stabilized intermediates, H2O3 and H2O4

“…The latter should have about the same lengths ( -1.5 A) as in hydrogen peroxide, and 0-0-0 angles of 100 to 120". Internal rotation of the O H groups would be only weakly hindered in the free molecules; in the solid their orientation will be strongly dependent on hydrogen bonding, again as in hydrogen peroxide (37).…”