Coulomb fission

The elder model of ion formation, the charged-residue model (CRM), assumes the complete desolvation of ions by successive loss of all solvent molecules from droplets that are sufficiently small to contain just one analyte molecule in the end of a cascade of Coulomb fissions. [9,42,84] The charges (protons) of this ultimate droplet are then transferred onto the molecule. This would allow that even large protein molecules can form singly charged ions, and indeed, CRM is supported by this fact. [23]... 

Duft, D. Achtzehn, T. Muller, R. Huber, B.A. Leisner, T. Coulomb Fission. Rayleigh Jets From Levitated Microdroplets. Nature 2003,421,128. 

Brechignac C, Cahuzac P, Keballl N and Leygnler J 1998 Temperature effects In the Coulombic fission of strontium clusters Phys. Rev. Lett. 81 4612... 

D. Duft, T. Achtzehn, R. Muller, B. A. Huber, and T. Leisner, Coulomb fission. Rayleigh jets from levitated microdroplets, Nature, 421 (2003) 128. 

FIGURE 22.6 Effect of charge density on Coulomb fission of solidifying particles produced by EHDA process. 

Thomson 1979), the charge on droplets of this size that is required for this ion evaporation is lower than that required for Coulomb fission, i.e., ion evaporation replaces Coulomb fission as a means of relaxing the Coulombic repulsion at the droplet surface. The equation predicting the rate constant for ion evaporation from the droplets was derived on the basis of the transition state theory (see any text on physical chemistry) ... 

Isotopes investigated in low-energy fission are indicated on the chart of nuclides. Circles Mass distributions measured for excitation energies less than 10 MeV above the fission barrier and those from SF. Crosses Data obtained using the Coulomb fission by using the relativistic radioactive beams (Schmidt et al. 2000)... 

Solvent Evaporation from Charged Droplets Causes Coulomb Fissions of Droplets... 

Most experiments used Phase Doppler Interferometry (PDI), a method well suited for volatile solvents as used in ESI-MS [27]. A series of PDI measurements using various solvents are given in Table 1.2. One can deduce from this table that the dependence on the type of solvent is relatively small. Thus, droplets from all solvents experience Coulomb fissions close to, or at, the Rayleigh limit. The loss of mass on fission is between 2 and 5% of the parent droplet mass but the loss of charge is much larger, that is, some 15-25% of the charge of the parent droplet. 

Evaporation of Droplets Leading to Coulomb Fissions Producing Progeny Droplets that Ultimately Lead to Ions in the Gas-Phase Effects of the Concurrent Large Concentration Increase... 

Figure 1.6 Predictions of the ion evaporation theory [34]. The Rayleigh curve provides the droplet radius R and the number of elementary charges N at w/hich a charged water droplet will be at the Rayleigh limit. Solvent evaporation at constant charge to a smaller radius R will cause a Coulomb fission. Similarly, the curves Cation Cluster and Anion Cluster show the threshold of ion evaporation at a given charge N and droplet radius R. For negatively charged droplets,...

Femdndez de la Mora, J., On the outcome of the Coulombic fission of a charged isolated drop, J. Coll. Interface Sci., accepted, 1995. 

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