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CemGEMS user guide

List of chemical elements used in recipe and GEM equilibration calculations

Element Molar mass Notes
Al 26.98154 in g/mol
B 10.812
Ba 137.328
Br 79.904
C 12.0108
Ca 40.078
Cl 35.453
F 18.9984
Fe 55.845
H 1.00795
K 39.0983
Li 6.941
Mg 24.305
Mn 54.938
N 14.0067 reactive nitrogen (nitrates etc.)
Na 22.9898
Nit 14.0067 non-reactive air nitrogen
O 15.9994
P 30.9738
S 32.067
Si 28.0855
Sr 87.620
Ti 47.880
Zz 0 electric charge (balance)

Molar masses are used in automatic recalculations between mole-based and mass-based values at all levels of recipe objects. This list should cover 99.99% of available chemical data on cementitious systems. All other elements, if entered in the formulae, will result in errors and failure of calculations. Such elements, if present in your own data, can be ignored or added to analogous elements, for example, the quantity of Rb added to quantity of K. Compositions of constituents or materials given in %% units will be automatically rescaled to 100% sum and corrected in the recipe before the GEM equilibration.

Most template compositions of particular materials or their constituents, collected by experts from literature and reports, cover only part of the full list of chemical slements. The bulk elemental composition of the reactive sub-system is computed automatically from the whole tree of formulae, constituents, materials and the recipe. If amount of an element is zero, it will be substituted with 1e-9 mol before the GEM equilibrium state calculation. However, only elements, chemical species and phases with amounts greater than 1e-9 are shown in Results tables. In plots, normally only masses or volumes of phases greater than 0.3% of the total are shown.

Lists of names and indices of materials and constituents used in recipe templates

The harmonized lists of names and indices (in tables below) were introduced since v.0.6.1 release of CemGEMS. They reduce much the adjustments in process definition documents that the user might need to do by editing. The names of constituents in the "Cement" material now begin with their acronyms in CCN (cement chemistry notation). This should make these names more familiar to cement chemists. The names of constituents in the "SCM" material now start with the acronyms that are commonly used in cement industry and research.

To retain the consistency with process templates (used for creating new processes), we recommend by editing the recipe:

  • If a constituent is not needed: to set its Quantity to 0 in the tree-like table instead of deleting this constituent in jsoneditor;

  • If a constituent is missing and needs to be added using jsoneditor: to append it to the constituents list instead of inserting it in the middle of the list.

Target path examples (in Process spans), the index of recipe in templates is always 0

  • To “Cement” material quantity: "targetPath": “/recipes/0/materials/0/Quantity”

  • To “SCM” material, “FA_Fly_ash_reactive” constituent reaction extent: "targetPath": “/recipes/0/materials/1/constituents/4/ReactExtent”

All recipe templates of “min” data type except “Minimal” and “Primitive”

Material Index Constituent Index Notes
Cement 0 C3S_Alite 0 real
0 C2S_Belite 1 real
0 C3A_Aluminate 2 real
0 C4AF_Ferrite 3 real
0 M_Periclase 4 pure
0 C_Lime 5 pure
0 Cc_Calcite 6 pure
0 Cs_Anhydrite 7 pure
0 CsH2_Gypsum 8 pure
0 Ks_Arcanite 9 pure
0 Ns_Thenardite 10 pure
0 K3Ns2_Aphtitalite 11 pure
0 CaF2_Fluorite 12 pure

Only “CSA-C”, “BYF-C” & “CAC-Fe” recipe templates of “min” data type

Material Index Constituent Index Notes
Cement 0 CT_Perovskite 13 pure
0 C4A3s_Ye^elimite 14 pure
0 C5S2s_Ternesite 15 pure
0 C2AS_Gehlenite 16 pure
0 C12A7_Mayenite 17 pure
0 CA_Monoaluminate 18 pure
0 CA2_Dialuminate 19 pure
0 MA_Spinel 20 pure
0 CMc2_Dolomite 21 pure
0 C2F_Ca2Fe2O5 22 pure
0 Fe3O4_Magnetite 23 pure
0 C3FT_Ferrititanate 24 pure
0 C20A26M3S3_Pleochroite 25 pure

All recipe templates except “Minimal” and “Primitive”

Material Index Constituent Index Notes
SCM 1 LS_Limestone 0 real
1 SF_Silica_fume 1 real
1 GGBFS_Slag_reactive 2 real
1 CC_Calcined_clay 3 real
1 FA_Fly_ash_reactive 4 real
1 PZ_Pozzolan 5 real
1 Anh_Anhydrite 6 pure
1 Gp_Gypsum 7 pure
1 Hh_Hemihydrate 8 pure
1 Qtz_Quartz 9 pure
1 GGBFS_Slag_inert 10 real, CEM-III only

All recipe templates of “min” data type except “Minimal” and “Primitive”

Material Index Constituent Index Notes
Water 2 Lab_water 0 real
2 Electrolyte 1 pure
2 Freshwater 2 real
2 Seawater 3 real
2 Brackwater 4 real

All recipe templates except “Minimal” and “Primitive”

Material Index Constituent Index Notes
Salts 3 CO2 0 pure
3 Sea_salt 1 real
3 NaCl 2 pure
3 Na2SO4 3 pure
3 Na2CO3 4 pure
3 KCl 5 pure
3 K2SO4 6 pure
3 K2CO3 7 pure
3 LiCl 8 pure
3 Li2SO4 9 pure
3 Li2CO3 10 pure
3 MgCl2 11 pure
3 MgSO4 12 pure
3 H3BO3 13 pure
3 H2SO4 14 pure
3 HCl 15 pure
3 HF 16 pure
3 HNO3 17 pure