Editing RWFF model of water

The '''RWFF''' (reactive water force field) [[water]] model <ref>[http://dx.doi.org/10.1016/j.cplett.2007.09.063 Detlef W.M. Hofmann, Liudmila Kuleshova and Bruno D’Aguanno "A new reactive potential for the molecular dynamics simulation of liquid water", Chemical Physics Letters '''448''' pp. 138-143 (2007)]</ref>. This [[Force fields |force field]] allows, in combination with classical [[molecular dynamics]], the calculation of macroscopic physical properties and, in particular, of the [[conductivity]]. The classical approach is favourable in [[Computer simulation techniques |simulations]], because  the conductivity is a cooperative effect involving  all of the charged particles in a given system. Therefore the simulations have to include a large number of atoms and have to be repeated sufficiently in order to obtain  significant statistics. The ability of RWFF  to properly describe the proton transfer between hydronium and water molecule, as well as other [[Physical properties of water |properties of water]] has been shown by simulations on a Nafion membrane <ref>[http://dx.doi.org/10.1007/s00894-007-0265-9 Detlef W. M. Hofmann & Liudmila Kuleshova & Bruno D’Aguanno "Molecular dynamics simulation of hydrated Nafion with a reactive force field for water", Journal of Molecular Modeling  '''14''' pp. 225-235 (2008)]</ref>. The kinetics of the proton transfer is found to be of the second order, and the elevated conductivity in membranes is well reproduced.

*[http://dx.doi.org/10.1016/j.jpowsour.2009.10.019 D.W.M. Hofmann, L.N. Kuleshova , B. D’Aguanno "Theoretical simulations of proton conductivity: Basic principles for improving the proton conductor", Journal of Power Sources '''195''' pp. 7743-7750 (2010)]