In chemical kinetics, the pre-exponential factor or A factor is the pre-exponential constant in the Arrhenius equation (equation shown below), an empirical...

reaction), T is the absolute temperature, A is the pre-exponential factor or Arrhenius factor or frequency factor. Arrhenius originally considered A to be a...

ratio between the pre-exponential factor and the collision frequency, and it is most often less than unity. Physically, the steric factor can be interpreted...

pre-exponential factor and the activation energy at several coverages. This calculation can be simplified. First we assume the pre-exponential factor...

to understand the two parameters associated with this law, the pre-exponential factor (A) and the activation energy (Ea). TST, which led to the Eyring...

gives a straight line, from which the activation energy and the pre-exponential factor can both be determined. The Arrhenius equation can be given in the...

{\displaystyle k=Ae^{{-E_{\textrm {a}}}/{(RT)}}} where A is the pre-exponential factor for the reaction, R is the universal gas constant, T is the absolute...

{-(\Delta G^{0}+\lambda )^{2}}{4\lambda kT}}\right],} with A being the pre-exponential factor, which is usually experimentally determined, although a semi-classical...

the Arrhenius equation. The Evans–Polanyi model assumes that the pre-exponential factor of the Arrhenius equation and the position of the transition state...

or A) magnetic vector potential (A) mass number of a nuclide (A) pre-exponential factor (A) one of the reciprocal lattice vectors (a*) relative atomic mass...

positive pre-exponential factor and will be equivalent to τ {\displaystyle \tau } but the second one will have a negative pre-exponential factor resulting...

the subsurface at x = 0 {\displaystyle x=0} is simplified to the pre-exponential factor of the distribution ( ∂ C ∂ x ) x = 0 = C b π D t . {\displaystyle...

with e−Ea⁄RT. The constant of proportionality A is the pre-exponential factor, or frequency factor (not to be confused here with the reactant A) takes into...

of the activation energy, but mainly because of the unfavorable pre-exponential factor of the rate constant. Although hydrogenation is endothermic, this...

{E_{\mathrm {a} }}{RT}}\right)} where A, is the pre-exponential factor or frequency factor, exp is the exponential function, Ea is the activation energy, R is...

{\displaystyle k=Ae^{-E_{\rm {a}}/(RT)}} , where A is the pre-exponential factor or A-factor, Ea is the activation energy, R is the molar gas constant...

^{-6285.5/RT}\\k_{3f}&=3.80\times 10^{13}\end{aligned}}} where the pre-exponential factor is measured in units of cm, mol, s and K (these units are incorrect)...

every kind of diffusion process for the de-trapped carriers, the pre-exponential factor in the Poole–Frenkel formula is thus proportional to E {\displaystyle...

{S_{\mathrm {eff} }}{\hbar }}\right)} with the effective action Seff and pre-exponential factor Ao. This form is specifically useful in a dissipative system, in...

parameters for describing the reactions: Between the logarithm of the pre-exponential factors (or prefactors) and the activation energies ln ⁡ A i = α + E a...

n is the order of desorption, υ {\displaystyle \upsilon } the pre-exponential factor, E is the activation energy, R is the gas constant and T is the...

{2a_{1}a_{2}}{a_{1}+a_{2}}}\right]e^{\frac {-(R-a_{1}-a_{2})}{L}}} where As is the pre-exponential factor (1.5 × 10−3 J⋅m−2) and L is the decay length (1 × 10−9 m). This...

without making the charge transfer. 2. It provides a formula for the pre-exponential factor in the Arrhenius equation, based on the electronic coupling between...

Y_{O_{2}}}{W_{O_{2}}}}\right)^{n}e^{-E_{a}/RT},} where B {\displaystyle B} is the pre-exponential factor, ρ {\displaystyle \rho } is the density, Y F {\displaystyle Y_{F}}...

Fowler–Nordheim Constant, is given by This shows clearly that the pre-exponential factor aφ−1F2, that appears in Fowler–Nordheim-type equations, relates...

constant atomic weight, denoted by Ar work in classical mechanics the pre-exponential factor in the Arrhenius Equation electron affinity A {\displaystyle \mathbb...

numerical calculations of liquid molar volume by an imperfect EOS. The pre-exponential factor A is now a function and becomes A = L c ρ ( α ρ + P V ) 3 M R T...

curve which is described using the Power Law model where ‘A’ is a pre-exponential factor. d a / d N = A ( K ) m {\displaystyle da/dN=A(K)^{m}} (Power Law...

energy) Reaction still proceeds at lower temperatures. The Arrhenius pre-exponential factors AD/AH is not equal to 1. A large negative entropy of activation...

{\displaystyle A_{k}} and E k {\displaystyle E_{k}} , the Arrhenius pre-exponential factor and activation energy, respectively, are adjusted for specific reactions...