Complete dipole oscillator strength distribution and its moments for N2

Abstract

Articles you may be interested inElectronic transition dipole moments and dipole oscillator strengths within Fock-space multi-reference coupled cluster framework: An efficient and novel approach J. Chem. Phys. 138, 094108 (2013); 10.1063/1.4793277 Ozone: Unresolved discrepancies for dipole oscillator strength distributions, dipole sums, and van der Waals coefficients J. Chem. Phys. 135, 074303 (2011); 10.1063/1.3626523 Experimental determination of the moments of the generalized oscillator strength distribution of HeThe complete dipole oscillator strength distribution for N 2 has ~ee~ cal.culated using , the multiple scattering model. From this, the moments of the dIstnbutIon Sip) and Lip) have been computed for -6 ~f.L ~ 2. The results are analyzed by decomposing the total moments according to the contributions from various subshells and also according to the contributions from various spectral ranges, e.g., discrete ~s ionizi~g excitations. Since many physical properties depend on these moments, thIS analysIs can pinpoint the spectral ranges with the greatest influence. Special attention is devoted to the distinctly molecular etTects on the dipole oscillator strength distribution and its moments, particularly for those channels atTected by shape resonances. The Rydberg series, for example, are significantly atTected. This analysis otTers an explanation for the weakness of certain dipole allowed Rydberg series and suggests a tentative new assignment for Worley's third series.

Angular Momentum Sensitive Two-Center Interference

“…These oscillations directly reflect the l-phase difference of the individual orbitals. For N 2 the phase shift between the σ and the β oscillation is 0.6π whereas for O 2 this phase shift is close to π matching the literature values for the l-phase differences of atomic nitrogen and oxygen [26][27][28][29][30][31]. The orbital-averaged effective bond lengths for the valences are 0.094 and 0.084 nm for N 2 and O 2 , respectively, which suggests that the highly delocalized valence state has a smaller effective bond length compared to the equilibrium bond lengths.…”

Photoelectron angular distributions from rotationally resolved autoionizing states of N2

“…Figure 1 also includes bands corresponding to transitions to the b 1 Σ u + , v = 42-44 states, the (B 2 Σ u + )3sσ g , v = 0 state, an unassigned 1 Σ u + or 1 Π u state most likely having an A 2 Π u core, and the (X 2 Σ g + )9f, v = 1 state. [4][5][6][7][8][9][10][11][12] The latter is best described in Hund's case (d) 12,13 and is discussed in more detail later on. All of the former bands can be treated at least tentatively in Hund's case (a) or (b).…”

“…1,[5][6][7][14][15][16][17] This region contains a number of sharp bands along with two intense, broad-yet-structured, complex resonances that have been said to have the appearance of two towers of a gothic cathedral. There is substantial agreement over the assignment of most of the sharp structure, and the lower energy tower has been assigned to a transition associated with the (B 2 Σ u + )3sσ, v = 0 final state; however, despite numerous theoretical 4,9,14,15 and experimental studies, no consensus has been reached for the assignment of the higher energy tower. These previous experiments include extremely high-resolution single-photon absorption and ionization of jetcooled N 2 , 5,16 photoionization from vibrationally excited levels of the neutral electronic ground state, 1 double-resonance studies via the a 1 Π g state, [10][11][12] and comprehensive studies using isotopic substitution.…”

“…In N 2 , the fσ and fπ components of the f states are more penetrating, but experiments still show that the np Rydberg series are much stronger than the corresponding nf series. 4,9 Indeed, the bands associated with transitions to nf final states are strongest when they gain intensity through perturbations by Rydberg states converging to the A 2 Π u ionic state. 4 Thus, near threshold, direct photoionization in N 2 should be dominated by the p continua.…”

“…[1][2][3][4][5][6][7] This relatively large number of states can lead to complex resonance features that are perturbed with respect to intensities, linewidths, and expected level positions. Thus, while considerable progress has been made in the analysis of this region of the N 2 spectrum, [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] some strong features still lack definitive spectral assignments. Perhaps the most noteworthy of these regions lies between ∼126 200 and 126 500 cm 1 in the single-photon ionization spectrum.…”