Rotational line strengths in 3Δ–3Σ electronic transitions. The Herzberg III system of molecular oxygen

C. M. L. Kerr; J. K. G. Watson

doi:10.1139/p86-006

Rotational line strengths in 3Δ–3Σ electronic transitions. The Herzberg III system of molecular oxygen

Canadian Journal of Physics ◽

10.1139/p86-006 ◽

1986 ◽

Vol 64 (1) ◽

pp. 36-44 ◽

Cited By ~ 23

Author(s):

C. M. L. Kerr ◽

J. K. G. Watson

Keyword(s):

Molecular Oxygen ◽

Satisfactory Agreement ◽

Electronic Transitions ◽

Rotational Line ◽

Spin Orbit ◽

First Order ◽

Order Relations ◽

Transition Moments ◽

Wave Numbers ◽

Line Strengths

Electronic transitions of the type 3Δ–3Σ are forbidden in the absence of spin–orbit or orbit–rotation coupling, but spin–orbit perturbations produce three transition moments, two perpendicular (Y1 and Y2) and one parallel (Z1) while low-order orbit–rotation couplings introduce three further perpendicular transition moments (X1, X2, and X3). Formulas are presented for the rotational line strengths in a 3Δ(a)–3Σ(int) transition in terms of these parameters and are applied to recent data of Coquart and Ramsay for the Herzberg III system [Formula: see text] of molecular oxygen. It is shown that all six parameters are significant, and that there are noticeable departures from the first-order relations Y1 = Y2, Z1 = 0, X1 = X2 = X3. The observation of orbit–rotation intensity effects led to the first identification of lines of the Ω′ = 3 subbands of the 4–0 to 7–0 bands of the Herzberg III system, which are forbidden for the spin–orbit mechanism. The wave numbers of these lines are in satisfactory agreement with the analysis of the A′3Δu → a1Δg emission by Slanger and Huestis.

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Rotational line strengths in 3Σ+–3Σ− electronic transitions. The β3Σu+ – X3Σg− and A3Σu+ – X3Σg− systems of molecular oxygen

Canadian Journal of Physics ◽

10.1139/p90-034 ◽

1990 ◽

Vol 68 (2) ◽

pp. 231-237 ◽

Cited By ~ 12

Author(s):

B. R. Lewis ◽

S. T. Gibson

Keyword(s):

Molecular Oxygen ◽

The Other ◽

Orbit Coupling ◽

Electronic Transitions ◽

Rotational Line ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Other Hand ◽

Line Strengths

Rotational line strengths are given for 3Σ+(int) – 3Σ−(int) transitions arising from spin–orbit coupling. Observed branch intensities for the forbidden β3Σu+ – X3Σg− transition of O2 may be explained by assuming spin–orbit mixing of β3Σu+ with the B3Σu− and E3Σu− states. On the other hand, observed branch intensities for the Herzberg I A3Σu+ – X3Σg− transition of O2 may be explained only by assuming mixing with 3Σ and 3Π states. In neither case do earlier formulae, derived assuming a single 3Π perturber, apply.

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Rotational line intensities in 3Σ–1Σ electronic transitions

Canadian Journal of Physics ◽

10.1139/p68-491 ◽

1968 ◽

Vol 46 (14) ◽

pp. 1637-1643 ◽

Cited By ~ 114

Author(s):

James K. G. Watson

Keyword(s):

Electronic Transitions ◽

Spin Interaction ◽

Rotational Line ◽

Line Intensities ◽

Transition Moments ◽

Linear Molecules

Formulae are given for the intensities of rotational lines in 3Σ–1Σ electronic transitions of linear molecules, allowing for the effects of spin–spin interaction. For [Formula: see text] transitions an error in the relative phases of the two transition moments in the work of Schlapp (1932) is corrected. Recent observations on SO and HCP support this change in phases.

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Rotational Line Strengths in 3Σ±–3Σ± Transitions with Intermediate Coupling

Canadian Journal of Physics ◽

10.1139/p71-325 ◽

1971 ◽

Vol 49 (21) ◽

pp. 2693-2703 ◽

Cited By ~ 105

Author(s):

J. B. Tatum ◽

J. K. G. Watson

Keyword(s):

Magnetic Dipole ◽

Electric Dipole ◽

Diatomic Molecules ◽

Transition Moment ◽

Rotational Line ◽

Intermediate Coupling ◽

Group Vi ◽

Transition Moments ◽

Splitting Constant ◽

Line Strengths

Rotational line strengths (Hönl–London factors) are calculated for 3Σ±–3Σ± electric dipole transitions, allowing for nonzero values of the splitting constant λ. If the 3Σ states are intermediate between Hund's coupling cases (a) and (b) only one transition moment is required, whereas if there is a tendency to case (c) four transition moments may be required. The resulting formulas are compared with the observed spectra of the diatomic molecules of the Group VI elements. The same formulas are valid for 3Σ±–3Σ± magnetic dipole transitions.

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SEMIEMPIRICAL SCF–LCAO–MO TREATMENT OF THIOPHENE, FURAN, AND PYRROLE

Canadian Journal of Chemistry ◽

10.1139/v65-208 ◽

1965 ◽

Vol 43 (5) ◽

pp. 1569-1576 ◽

Cited By ~ 61

Author(s):

N. Solony ◽

F. W. Birss ◽

John B. Greenshields

Keyword(s):

Experimental Data ◽

Satisfactory Agreement ◽

Electronic Structures ◽

Spectroscopic Data ◽

Variable Parameter ◽

Coulomb Repulsion ◽

Resonance Integral ◽

Electronic Transitions ◽

The Core ◽

Lcao Mo

The semiempirical SCF–LCAO–MO method of Pariser–Parr–Pople is utilized in the study of the π-electronic structures of thiophene, furan, and pyrrole. The core Hamiltonian expansion contains a Uz++ term, the potential due to the ionized hetero-atom contributing two electrons to the π-system. The γzz, one-center coulomb repulsion integral for the hetero-atom is evaluated from the experimental spectroscopic data only. With the resonance integral βczc as the only variable parameter, the calculated π*–π electronic transitions are in a satisfactory agreement with the experimental data.

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Interpretation of Electron Transfer Spectra of Iridium (IV) and Osmium(IV) Mixed Chloro-Bromo Complexes

Zeitschrift für Naturforschung A ◽

10.1515/zna-1967-0614 ◽

1967 ◽

Vol 22 (6) ◽

pp. 945-954 ◽

Cited By ~ 8

Author(s):

Chr. Klixbüll Jørgensen ◽

W. Preetz

Keyword(s):

Electron Transfer ◽

Faraday Effect ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

University Of Virginia ◽

First Order ◽

Order Of Magnitude ◽

Moderate Difference ◽

The University ◽

As If

The previous M.O. treatment of unsubstituted hexahalides has been modified, taking the results on Faraday effect obtained at the University of Virginia into account. The absorption spectra previously measured of the complexes (M=Os, Ir) trans-MCl4Br2— and trans-MCl2 Br4— are interpreted by a M.O. treatment for the symmetry D4h as electron transfer transitions, including a first-order relativistic (spin-orbit coupling) correction. The concept of holohedrized symmetry is sufficiently valid to allow a description of MCl5Br— and MClBr5— as if they were tetragonal with centre of inversion and ƒac-(or cis-)MCl3Br3— as if they were cubic. It is shown that the ligand-ligand antibonding effects have the same order of magnitude as the moderate difference in optical electronegativity between Cl- and Br-.

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Rotational line strengths in4Σ-4Π transition of diatomic molecules

Pramana ◽

10.1007/bf02894851 ◽

1985 ◽

Vol 24 (3) ◽

pp. 503-512

Author(s):

T K Balasubramanian ◽

V P Bellary

Keyword(s):

Diatomic Molecules ◽

Rotational Line ◽

Line Strengths

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Rotational line strengths in a 5Σ – 5Π transition with application to the A – X system of CrO

Canadian Journal of Physics ◽

10.1139/p84-206 ◽

1984 ◽

Vol 62 (12) ◽

pp. 1610-1615 ◽

Cited By ~ 10

Author(s):

U. Sassenberg ◽

A. S.-C. Cheung ◽

A. J. Merer

Keyword(s):

Transition Moment ◽

Rotational Line ◽

Π State ◽

Strong Spin ◽

Line Strengths

Detailed calculations of the line strengths in a 5Σ – 5Π transition as a function of J show that the relative branch intensities in the A – X system of CrO, which do not follow the published formulae for 5Σ(b) – 5Π(a) transitions, can be explained very well in terms of strong spin uncoupling in the 5Π state, with a single perpendicular transition moment dominating. It is emphasized that spin uncoupling affects line strengths by an amount that increases very rapidly with multiplicity, so that algebraic formulae for the pure coupling cases quickly lose their value. An unusual cancellation effect occurs in the main branches of a 5Σ – 5Π transition, nine of which have intensities that drop to zero and then rise again with increasing J.

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