Photoelectron Spectra of F2O and Cl2O

Abstract

The valence ionization potentials of F2O and Cl2O have been determined by photoelectron spectrometry, and the results are compared with the predictions of ab initio and approximate LCAO SCF calculations. The first PES band shows vibrational structure which is assigned to ν1 for F2O, and to both ν1 and ν2 for (Cl2O). These frequencies all show slight increases over the corresponding values for the ground states of the neutral molecules.

Photoelectron Spectra of Phosgene and Thiophosgene

“…When this is taken into account the following order is obtained: 3b1, 7b2, 2a2, lla,, which is also that predicted by the CND0/2 calculations. However, since the a, orbital was concluded to be the highest binding energy chlorine non-bonding level in C1,CS and C120 (15,16), this must be true of C1,CO where the o ionizations are at slightly lower binding energies than in C1,O. The observed progression in v, is consistent with the assignment of 13.50 eV I.P.…”

“…An interpretation of the p.e. spectrum of C1,O places the a, chlorine non-bonding level above the a, (15,16). This inversion of the order on the basis of overlap considerations is attributed to a small interaction of the chlorine a, orbital with an a, a bonding orbital at higher binding energy (16).…”

The X̃ 2B1, B22, A12, and A22 states of oxygen difluoride cation (F2O+): High-level ab initio calculations and simulation of the ultraviolet photoelectron spectrum of F2O

“…Nevertheless, with the aid of spectral simulations, which employ our recently developed anharmonic FranckCondon ͑FC͒ code, 11 most of the observed vibrational structure of this band could be adequately accounted for, and a reasonably reliable order of the five cationic states involved was proposed. In the present study on the He I PE spectrum 1 or b 2 in the C 2V point group corresponds to being symmetrical with respect to the molecular plane, depends on the choice of the axes system. Brundle and co-workers ͑Ref.…”

“…Some of the computed VIEs reported for the lowest four cationic states [1][2][3][4][5][6][7][8][9] are summarized in Table I ͑see footnote a͒. From Table I, it is clear that the assignment of the 2 B 1 state of F 2 O ϩ to the first observed PE band is reasonably certain.…”

“…1 The observed bands were assigned with the aid of results of INDO and CNDO/2 semi-empirical calculations, and previous ab initio calculations ͑see Ref. 1 for details͒.…”