Waldmann-Snider equation

Snider is best known for his paper reporting what is now referred to as the Waldmann-Snider equation.34 (L. Waldmann independently derived the same result via an alternative method.) The novelty of this equation is that it takes into account the consequences of the superposition of quantum wavefunctions. For example, while the usual Boltzmann equation describes the collisionally induced decay of the rotational state probability distribution of a spin system to equilibrium, the modifications allow the effects of magnetic field precession to be simultaneously taken into account. Snider has used this equation to explain a variety of effects including the Senftleben-Beenakker effect (i.e., is, the magnetic and electric field dependence of gas transport coefficients), gas phase NMR relaxation, and gas phase muon spin relaxation.35... 

The fiilly quantum-mechanical kinetic theory of polyatomic gases is based on the Waldmann-Snider equation (Waldmann 1957 Snider 1960) and was subsequently developed and sununarized by McCourt and co-workers (for instance, McCoiut et al. 1990,1991). Wang Chang and Uhlenbeck (1951) and independently de Boer (see Wang Chang et al. 1964) formulated a semiclassical kinetic theory (Wang Chang-Uhlenbeck-de Boer theory, or WCUB) subsequently developed by Monchick, Mason and their col-... 

The original Chapman-Enskog theory is based on the Boltzmann equation (Boltzmann 1872) that was developed for structureless particles which exhibit isotropic intermolec-ular potentials. Monatomic species are a subset of polyatomic molecules that do not possess modes of internal motion and interact via elastic collisions only. This simplifies the problem dramatically because the WCUB equation (or Waldmann-Snider equation) can be replaced by the Boltzmann equation that is solved in its linearized form. 

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See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

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