Enthalpy of Mackinawite precipitaion

[Sifat Azad Papry]

Hi,
I need to know the enthalpy value (delta_h) value of mackinawite precipitation to simulate the effect of temperature. But in PhreeqC database I only see the log K value. As such, could you please inform me in which database I can find the delta_h value and where can I find the database? Thanks.

[dlparkhurst]

The thermoddem database at https://thermoddem.brgm.fr/ has the following definition:

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Mackinawite
FeS + 1.000H+ = 1.000Fe+2 + 1.000HS-
     log_k    -3.540     
     delta_h  -10.805    #kJ/mol        #Internal calculation
     -analytic -9.7649376E+2  -1.5351306E-1  5.3325155E+4  3.5339847E+2  -3.0749343E+6

You could also check databases for Pyrrotite, which is also FeS.