Open-source · Peer-reviewed · Free

Geochemical models
for soil and water

Quantitative tools for adsorption equilibria, ion binding, competitive transport, and speciation in soils, sediments, and groundwater. Based on established surface complexation models. (In Developing, Mistakes Possible!!!)

Browse Tools NICA-Donnan Model
11
Modelling tools
4
Core SCM engines
Free
Open-source
Browser
No installation

Core Tools

Surface complexation & transport

NICA-Donnan Model
Non-ideal competitive adsorption (NICA) combined with Donnan electrostatic model for humic substance binding. Industry standard for natural organic matter.
Live NICA · SCM
CD-MUSIC Model
Charge Distribution MUSIC model for ion adsorption at mineral-water interfaces. Validated for iron oxides, clays, and aluminum oxides.
Live CD-MUSIC · SCM
LCD / Ligand and Charge Distribution
Ligand and Charge Distribution.
Live LM · SCM
Multi-Surface SCM
Couple NICA-Donnan, CD-MUSIC, and electrostatic models across multiple mineral and organic surfaces simultaneously.
Beta Coupled SCM
Three-Site NICA-Donnan
Explicit proton and metal binding across strong, weak, and very weak sites on humic substances. Extended NICA parameterization.
Live NICA · Extended
NOM-CD
Natural organic matter characterization using charge distribution modeling.links structural composition to observable binding behavior.
Beta NOM · Characterization
View all 11 tools

Scientific basis

Grounded in established surface chemistry

Carbon4Planet tools implement formally published model formulations — NICA-Donnan, CD-MUSIC, Ligand and Charge Distribution, and related approaches — documented in peer-reviewed literature. Parameters are sourced from the literature or fitted to experimental data you provide.

Models are intended for research and educational use. Results should be interpreted in the context of model assumptions and parameter uncertainty.

Model coverage
NICA-DonnanHumic substances
CD-MUSICFe/Al oxides, clays
Ligand and Charge DistributionSimple ligands
WHAM / NICA-DonnanHM binding to DOM
3-Site NICAProton heterogeneity

About

Quantitative Soil Geochemistry, delivered in the browser

Carbon4Planet provides free, browser-based tools for environmental chemists, soil scientists, and geohydrologists working on reactive transport, adsorption equilibria, and speciation modeling. No software installation, no license fees, no platform lock-in.

The project is developed and maintained as part of academic research. All tools are open-source and designed for reproducibility in environmental modeling.

Quick links