Rayleigh limit of charge

Here (7, is the surface tension, and Sq is the permittivity of free space. The mode n = 0 corresponds to the equilibrium sphere, and n = 1 is a purely translational mode. The first unstable mode is n = 2. The critical charge for this mode is given by setting Eq. (37) to zero, which yields the Rayleigh limit of charge,... 

Davis, E. J. Bridges, M. A. The Rayleigh limit of charge revisited light scattering from exploding droplets. 

Reference Solvent Droplet diameter range (pm) Onset of Instability (% of Rayleigh limit) % of mass lost in breakup" % of charge lost in breakup... 

Fenn and co-workers described electrospray ionization for mass spectrometry analyzing large biomolecules. ESI greatly enhanced MS ability for analysis of proteins or peptides. The mechanism of the ESI source is relatively simple. In an electrospray ionization source, the solution of analytes is nebulized into fine droplets via a capillary tube under a high electric field. The positive charges are accumulated on the surface of the droplets in this field. Later, because of evaporation of droplets, the surface coulombic forces exceed the surface tension and the droplets are dissociated into smaller droplets. This process continues until nanometer-sized droplets are formed. In this way, the ions pass from the source into the mass analyzer, whereas the bulk solvent is pumped away by a vacuum system. The stability limit (Rayleigh limit) of droplets is determined by the Coulomb forces of the accumulated positive... 

The rival theory of Iribame and Thomson54 assumes that gas-phase ions solvated by a few solvent molecules are emitted into the gas phase by charged droplets with radii R < 10 nm, which are somewhat below the Rayleigh limit. This ion evapora-... 

With a liquid droplet this maximum charge cannot be reached except in the case of extremely small droplet sizes. This is because of an additional charge limitation placed on liquid aerosols, known as the Rayleigh limit. It has been known for many years that as a highly charged droplet evaporates, a point will be reached where the outward force of the electric field at the drop surface exceeds the inward force of the droplet s surface tension. At this point, the drop will be torn apart by the close proximity of like charges and will produce a number of smaller drops in order to create more surface area for the charge. The number of electrons necessary for droplet... 

Later on, Iribarne and Thomson proposed a different mechanism for the production of gas-phase ions from charged droplets [27,28]. Interestingly, the motivation for their studies was far removed from a concern for the needs of mass spectrometry. Instead, it stemmed from their interest in charged droplets as a possible source of ions in the atmosphere. They proposed a model for such ion formation based on the idea that, on charged droplets that were small enough, evaporation could make the surface field sufficiently intense to lift solute ions from the droplet into the ambient gas before the Rayleigh limit is reached. This model is nowadays usually referred to as ion desorption model (IDM). 

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