Dataset of surface reactions for gwb programs
Dataset format: sep22
Surface type: Goethite
Model type: three-layer
Surface potential: n/a
Surface capacitance: 1.10  0.20  (Specify values of C1 and C2 in F/m2)
Thermo dataset: thermo.tdat
* 
* Example of a triple-layer reaction dataset: Selenite & selenate sorption onto goethite.
* 
* Based on data of Hayes et al. (1988).
* 
* Reference: Hayes, K.F., Papelis, C. and Leckie, J.O., 1988. Modeling ionic strength effects 
*  on anion adsorption at hydrous oxide/solution interfaces. Journal of Colloid and Interface
*  Science, 125(2), pp.717-726.
* 
* Hayes et al. (1988) suggested that only a subset of these reactions may be used to explain
* experimental results. 
* 
* This dataset considers inner-layer and outer-layer sorption of selenite and selenate onto Goethite. 
*  Reactions in GWB datasets are written in terms of destruction reactions. The values of logKs are
*  therefore negated from their corresponding literature values.
* 
* GWB releases 14.0 and later support bidentate and polydentate reactions according to
*  the stoichiometric, Davis-Leckie, Hiemstra-Van Riemsdijk, and Appelo-Postma conventions.
*  Refer to section "Polydentate sorption" in the GWB Essentials Guide.
* 
* GWB releases 14.0 and later accept site density values in units of either "mol/mol mineral"
*  or "sites/nm2".

-end-

   1 basis species

>FeOH
     charge=    0       mole wt.=    72.8543 g
     3 elements in species
        1.000 Fe              1.000 H               1.000 O       

-end-

   1 sorbing minerals

Goethite
     surface area= 52.0000 m2/g
     1 sorption sites
     >FeOH         site density=     7.0000 sites/nm2

-end-

   10 surface species

>FeOH2+
     charge0=   1       chargeb=   0     mole wt.=    73.8622 g
     2 species in reaction
        1.000 >FeOH           1.000 H+      
     log K    a=  -5.8000    b=  0.0   


>FeO-
     charge0=  -1       chargeb=   0     mole wt.=    71.8464 g
     2 species in reaction
        1.000 >FeOH          -1.000 H+      
     log K    a=  11.1000    b=  0.0   


>FeO-:Na+
     charge0=  -1       chargeb=   1     mole wt.=    94.8362 g
     3 species in reaction
        1.000 >FeOH           1.000 Na+            -1.000 H+      
     log K    a=  8.8000    b=  0.0   


>FeOH2+:NO3-
     charge0=   1       chargeb=  -1     mole wt.=   135.8671 g
     3 species in reaction
        1.000 >FeOH           1.000 NO3-            1.000 H+      
     log K    a=  -7.7000    b=  0.0   


>FeSeO3-
     charge0=  -1       chargeb=   0     mole wt.=   182.8052 g
     4 species in reaction
        1.000 >FeOH           1.000 SeO3--          1.000 H+      
       -1.000 H2O     
     log K    a=  -15.1000    b=  0.0   


>FeSeO3-:Na+
     charge0=  -1       chargeb=   1     mole wt.=   205.7950 g
     5 species in reaction
        1.000 >FeOH           1.000 SeO3--          1.000 H+      
        1.000 Na+            -1.000 H2O     
     log K    a=  -14.1000    b=  0.0   


>FeOH2+:HSeO3-
     charge0=   1       chargeb=  -1     mole wt.=   201.8283 g
     3 species in reaction
        1.000 >FeOH           1.000 SeO3--          2.000 H+      
     log K    a=  -21.8000    b=  0.0   


>FeSeO4-
     charge0=  -1       chargeb=   0     mole wt.=   198.8046 g
     4 species in reaction
        1.000 >FeOH           1.000 SeO4--          1.000 H+      
       -1.000 H2O     
     log K    a=  -8.8000    b=  0.0   


>FeOH2+:SeO4--
     charge0=   1       chargeb=  -2     mole wt.=   216.8198 g
     3 species in reaction
        1.000 >FeOH           1.000 H+              1.000 SeO4--  
     log K    a=  -8.9000    b=  0.0   


>FeOH2+:HSeO4-
     charge0=   1       chargeb=  -1     mole wt.=   217.8277 g
     3 species in reaction
        1.000 >FeOH           1.000 SeO4--          2.000 H+      
     log K    a=  -15.7000    b=  0.0   


-end-