Rotationally inelastic dynamics of LiH (X1Σ+, v = 0) in collisions with Ar: State-to-state inelastic rotational rate coefficients

AbstractA new way of critically assessing and compacting data for electron impact excitation of positive ions is proposed. This method allows one (i) to detect possible printing and computational errors in the published tables, (ii) to interpolate and extrapolate the existing data as a function of energy or temperature, and (iii) to simplify considerably the storage and transfer of data without significant loss of information. Theoretical or experimental collision strengths Ω(E) are scaled and then plotted as functions of the colliding electron energy, the entire range of which is conveniently mapped onto the interval (0,1). For a given transition the scaled Ω can be accurately represented - usually to within a fraction of a percent - by a 5 point least squares spline. Further details are given in (2). Similar techniques enable thermally averaged collision strengths upsilon (T) to be obtained at arbitrary temperatures in the interval 0 < T < ∞. Application of the method is possible by means of an interactive program with graphical display (2). To illustrate this practical procedure we use the program to treat Ω for the optically allowed transition 2s → 2p in ArXVI.

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Electron impact excitation of Al XIII : Collision strengths and rate coefficients

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:2001259 ◽

2001 ◽

Vol 11 (PR2) ◽

pp. Pr2-309-Pr2-312

Author(s):

K. M. Aggarwal ◽

F. P. Keenan ◽

S. J. Rose

Keyword(s):

Electron Impact ◽

Impact Excitation ◽

Rate Coefficients ◽

Electron Impact Excitation

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THE IONIZATION RATE COEFFICIENTS FOR SOME RADIATIVELY EXCITED RUBIDIUM STATES

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1979743 ◽

1979 ◽

Vol 40 (C7) ◽

pp. C7-87-C7-88

Author(s):

A. N. Klucharev ◽

A. V. Lazarenko ◽

V. Vujnovic

Keyword(s):

Ionization Rate ◽

Rate Coefficients

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Photoinduced Charge Transfer Dynamics in Carotenoid-Porphyrin-C60 Triad via the Linearized Semiclassical Nonequilibrium Fermi's Golden Rule

10.26434/chemrxiv.12519485.v1 ◽

2020 ◽

Author(s):

Zhengqing Tong ◽

Margaret S. Cheung ◽

Barry D. Dunietz ◽

Eitan Geva ◽

Xiang Sun

Keyword(s):

Charge Transfer ◽

Golden Rule ◽

Time Dependent ◽

Rate Coefficients ◽

Initial State ◽

Photoinduced Charge Transfer ◽

Transfer Rates ◽

Fermi's Golden Rule ◽

Photoinduced Charge ◽

Fermi’S Golden Rule

The nonequilibrium Fermi’s golden rule (NE-FGR) describes the time-dependent rate coefficient for electronic transitions, when the nuclear degrees of freedom start out in a <i>nonequilibrium</i> state. In this letter, the linearized semiclassical (LSC) approximation of the NE-FGR is used to calculate the photoinduced charge transfer rates in the carotenoid-porphyrin-C<sub>60</sub> molecular triad dissolved in explicit tetrahydrofuran. The initial nonequilibrium state corresponds to impulsive photoexcitation from the equilibrated ground-state to the ππ* state, and the porphyrin-to-C<sub>60</sub> and the carotenoid-to-C<sub>60</sub> charge transfer rates are calculated. Our results show that accounting for the nonequilibrium nature of the initial state significantly enhances the transition rate of the porphyrin-to-C<sub>60</sub> CT process. We also derive the instantaneous Marcus theory (IMT) from LSC NE-FGR, which casts the CT rate coefficients in terms of a Marcus-like expression, with explicitly time-dependent reorganization energy and reaction free energy. IMT is found to reproduce the CT rates in the system under consideration remarkably well.

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Reactivity Trends in the Gas Phase Addition of Acetylene to N-protonated Aryl Radical Cations

10.26434/chemrxiv.13078334 ◽

2020 ◽

Author(s):

Oisin Shiels ◽

P. D. Kelly ◽

Cameron C. Bright ◽

Berwyck L. J. Poad ◽

Stephen Blanksby ◽

...

Keyword(s):

Gas Phase ◽

Ion Trap ◽

Radical Cations ◽

Rate Coefficients ◽

Similar Process ◽

Ion Molecule Reactions ◽

Aromatic Radicals ◽

Polycyclic Aromatic ◽

Gas Phase Ion ◽

Type Radical

<div> <div> <div> <p>A key step in gas-phase polycyclic aromatic hydrocarbon (PAH) formation involves the addition of acetylene (or other alkyne) to σ-type aromatic radicals, with successive additions yielding more complex PAHs. A similar process can happen for N- containing aromatics. In cold diffuse environments, such as the interstellar medium, rates of radical addition may be enhanced when the σ-type radical is charged. This paper investigates the gas-phase ion-molecule reactions of acetylene with nine aromatic distonic σ-type radical cations derived from pyridinium (Pyr), anilinium (Anl) and benzonitrilium (Bzn) ions. Three isomers are studied in each case (radical sites at the ortho, meta and para positions). Using a room temperature ion trap, second-order rate coefficients, product branching ratios and reaction efficiencies are reported. </p> </div> </div> </div>

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State-of-the-Art of Modeling Surface Water Impoundments

Water Science & Technology ◽

10.2166/wst.1982.0061 ◽

1982 ◽

Vol 14 (1-2) ◽

pp. 241-261 ◽

Cited By ~ 7

Author(s):

P A Krenkel ◽

R H French

Keyword(s):

Water Quality ◽

Surface Water ◽

State Of The Art ◽

Rate Coefficients ◽

Two Dimensional ◽

One Dimensional ◽

Integral Energy ◽

Range Of Values ◽

Dimensional Integral ◽

Water Impoundment

The state-of-the-art of surface water impoundment modeling is examined from the viewpoints of both hydrodynamics and water quality. In the area of hydrodynamics current one dimensional integral energy and two dimensional models are discussed. In the area of water quality, the formulations used for various parameters are presented with a range of values for the associated rate coefficients.

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