CHINESE JOURNAL OF PHYSICS, vol.43, no.1, pp.103-109, 2005 (SCI-Expanded)
In this study we obtain a T-X phase diagram of Na2S2O7-NaHSO4 using the mean field theory. We fit our calculated phase line equation to the experimental T-X phase diagram. By choosing appropriately the coefficients in the free energy expansions, our calculated phase diagram agrees well with the experimentally observed phase diagram of Na2S2O7-NaHSO4.