Einsteins Law

Einstein law linear viscosity growth versus concentration... 

Quantum yield (d>) of molecular photodissociation in the gas phase is equal to unity according to the Einstein law. Frank and Rabinowitch [72] predicted the reduction of the quantum yield in a solution due to the cage effect. The quantum yield

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Stark-Einstein law of photochemical equivalence one photon of radiation can be absorbed only by one molecule [201,202]. 

In 1912, Einstein extended the concept of quantum theory of radiation to photochemical processes and stated that each quantum of radiation absorbed by molecule activates one molecule in the primary step of a photochemical process . This is known as Einstein law of photochemical equivalence. 

The Stark-Einstein law states that the primary act of light... 

According to the Stark-Einstein law, O should be equal to 1. However, if secondary reactions occur, can be greater than 1. 

Another microscopic approach to the viscosity problem was developed by Gierer and Wirtz (1953) and it is worthwhile describing the main aspects of this theory, which is of interest because it takes account of the finite thickness of the solvent layers and the existence of holes in the solvent (free volume). The Stokes-Einstein law can be modified using a microscopic friction coefficient ci micro... 

As seen in the preceding section, the counterions play a crucial role in the mobility of the polyelectrolyte molecules. Even in the absence of an external electric field, the counterions exert an induced electric field in the immediate environment of a charged segment which in turn significantly modifies the collective diffusion coefficient of the polymer. This additional contribution is absent for uncharged polymers, where the cooperative diffusion coefficient Dc is given by the Stokes-Einstein law in dilute solutions. 

Chromium(III) has a ground state in pseudo-octahedral symmetry. The absence of low-lying excited states excludes fast electron relaxation, which is in fact of the order of 10 -10 ° s. The main electron relaxation mechanism is ascribed to the modulation of transient ZFS. Figure 18 shows the NMRD profiles of hexaaqua chromium(III) at different temperatures (62). The position of the first dispersion, in the 333 K profile, indicates a correlation time of 5 X 10 ° s. Since it is too long to be the reorientational time and too fast to be the water proton lifetime, it must correspond to the electron relaxation time, and such a dispersion must be due to contact relaxation. The high field dispersion is the oos dispersion due to dipolar relaxation, modulated by the reorientational correlation time = 3 x 10 s. According to the Stokes-Einstein law, increases with decreasing temperature, and... 

Richert R, Pautmeier L, Bassler H (1989) Diffusion and drift of charge-carriers in a random potential - deviation from Einstein law. Phys Rev Lett 63 547... 

The second law of photochemistry was first enunciated by Stark (1908) and later by Einstein (1912). The Stark-Einstein law states that ... 

The second law is the Stark—Einstein law. whose re-statement in current terminology is that the primary photochemical act involves absorption of just one photon by a molecule. This holds true for the vast majority of processes exceptions to it arise largely when very intense light sources, such as lasers, are employed, and the probability of concurrent or subsequent absorption of two or more photons is no longer negligible. 

The Einstein law has been found to hold good in many examples. A summary of its application to reactions of various kinds has been given by Bodenstein,f and more recently by Allmand Trans. Faraday Soc., 1926, 438) its applicability to the decomposition of ozone under the influence of ultra-violet light has been shown by Warburg, X and it was shown to hold with considerable accuracy by Noddack in the reaction Cla + 2 CCl3Br = 2 CC14 + Br2, which is provoked by violet light. 

IV. The Einstein law is not even approximately obeyed. One quantum of fight brings about the union of many millions of molecules. 

Grottus-Draper law, 3 Lambert-Beer law, 3 second law, 5 Stark-Einstein law, 5 (of) metallocenes, 277... 

Photon energies can vary. Only one photon can be accepted at a time by an obtital. This is stated in the Stark-Einstein law also known as the Second Law of Photochemistry—if a species absorbs radiation, then one particle (molecule, ion, atom, etc.) is excited for each quantum of radiation (photon) that is absorbed. 

Stark-Einstein law, 4 Stem-Volmer plot, 34 slilbene, absorption spectrum, 1 3 cis-trans isomerization, 42 cvclization, 97 excited state energies, 17 styrenes, addition reactions, 58... 

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