Bmack Posted July 8, 2011 Share Posted July 8, 2011 I am trying to use React to mix the two waters in the attached script. I can't seem to get a proper charge balance. I have tried to move the ion on which I balance my charge to every ion in my basis water and I keep getting the same error: Residuals too large, 663-th iteration Largest residual(s): Resid Resid/Totmol Cbasis Cl- 0.07619 1.38e+200 5.456e-202 I even tried adding other ions that weren't part of the original water, but I get the same error. How do I get my charge to balance? Thanks! P5 at 365 days and recharge.rea Link to comment Share on other sites More sharing options...
Tom Meuzelaar Posted July 9, 2011 Share Posted July 9, 2011 Hi: It looks like the low pH is the reason for non-convergence. If you try a slightly higher pH (3.5), the script runs fine. Hope that helps, Tom Meuzelaar RockWare, Inc. Link to comment Share on other sites More sharing options...
Bmack Posted July 29, 2011 Author Share Posted July 29, 2011 Why does GWB force you to increase the pH to balance the reaction? Is there something in the GWB manual that explains this? What about other literature sources? Thanks! Link to comment Share on other sites More sharing options...
Tom Meuzelaar Posted August 1, 2011 Share Posted August 1, 2011 Hello: This isn't necessarily an issue with charge balance. It could be that you've defined a system that is far from equilibrium, and thus has trouble converging. If the pH value is important, I recommend starting with 3.5, so the system initially converges, then sliding the pH (in the Reactants pane) down to 3.1, so that you have a stable chemistry. Hope that helps, Tom Meuzelaar RockWare, Inc. Link to comment Share on other sites More sharing options...
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