Electrostatic field and charge distribution in small charged dielectric droplets
- 122 Downloads
The charge distribution in small dielectric droplets is calculated on the basis of continuum medium approximation. There are considered charged liquid spherical droplets of methanol in the range of nanometer sizes. The problem is solved by the following way. We find the free energy of some ion in dielectric droplet, which is a function of distribution of other ions in the droplet. The probability of location of the ion in some element of volume in the droplet is a function of its free energy in this element of volume. The same approach can be applied to other ions in the droplet. The obtained charge distribution differs considerably from the surface distribution. The curve of the charge distribution in the droplet as a function of radius has maximum near the surface. Relative concentration of charges in the vicinity of the center of the droplet does not equal to zero, and it is the higher, the less is the total charge of the droplet. According to the estimates the model is applicable if the droplet radius is larger than 10 nm.
Unable to display preview. Download preview PDF.
- Dole M., L.L. Mack, R.L. Hines, R.C. Mobley, L.D. Ferguson & M.B. Alice, 1968. Molecular beams of macroions. J. Chem. Phys. 49, 2240–2249.Google Scholar
- Gamero-Castano M. & J. Fernandez de la Mora, 2000. Mechanism of electrospray ionization of singly and multiply charged salt clusters. Analytica Chimica Acta. 406, 67–91.Google Scholar
- Gomez A. & K. Tang, 1994. Charge and fission of droplets in electrostatic sprays. Phys. Fluids. 6, 404–414.Google Scholar
- Iribarne J.V. & B.A. Thomson, 1976. On the evaporation of small ions from charged droplets. J.Chem. Phys. 64, 2287–2294.Google Scholar
- Labowsky M., J.B. Fenn & J. Fernandez de la Mora, 2000. A continuum model for ion evaporation from a drop: effect of curvature and charge on ion solvation energy. Analytica Chimica Acta. 406, 105–118.Google Scholar
- Rayleigh L., 1882. On the equilibrium of liquid conducting masses charged with electricity. Philos. Mag. 14, 184–186.Google Scholar
- Storozhev V.B. & E.N. Nikolaev, 2004. Computer simulations of the fission process of charged nanometre droplets. Philos. Mag. 84, 157–171.Google Scholar
- Tamm I.E., 1979. Fundamentals of the theory of electricity. Mir Publishers, Moscow.Google Scholar
- Widmamm J.F., C.L. Aardahl & E.J. Davis, 1997. Observations of non-Rayleigh limit explosions of electrodynamically levitated microdroplets. Aerosol Sci. & Technol. 27, 636–648.Google Scholar
- Zakharov V.V., E.N. Brodskaya & A. Laaksonen, 1998. Molecular dynamics simulation of methanol clusters. J. Chem. Phys. 109(21), 9487–9493.Google Scholar