Group-Contribution Properties estimates pure-component properties from structure alone, for molecules without measured data. It is the bridge from a molecule to the fluids and thermodynamics tools: its critical constants and acentric factor are what VLE / Flash and equation-of-state models need.
How it works
- Joback group contribution (the open-source
thermopackage) for boiling and melting points, critical temperature, pressure, and volume, formation enthalpy and Gibbs energy, enthalpies of vaporization and fusion, and ideal-gas heat capacity. - Ambrose correlation for the acentric factor ω, from the Joback boiling point and critical constants.
- RDKit Crippen for logP and molar refractivity.
Group-contribution estimates are approximations: errors of several percent (more for large or unusual molecules) are normal. Prefer measured values when you have them.
Inputs
Up to 10,000 SMILES. Set include_nasa7 to also get NASA-7 polynomial coefficients as a Cantera species snippet in the zip.
Outputs
properties.csv, one row per molecule, all SI:
| Column | Property |
|---|---|
tb_k, tm_k | Normal boiling and melting point (K) |
tc_k, pc_pa, vc_m3_mol | Critical temperature (K), pressure (Pa), and volume (m³/mol) |
omega | Acentric factor |
hf_j_mol, gf_j_mol | Ideal-gas enthalpy and Gibbs energy of formation (J/mol) |
hvap_j_mol, hfus_j_mol | Enthalpy of vaporization and of fusion (J/mol) |
cpig_a … cpig_d | Ideal-gas heat capacity polynomial coefficients |
crippen_logp, crippen_mr | Crippen logP and molar refractivity |
Molecules Joback can't break into groups keep their row with joback_status and an error; the job still succeeds.
Related tools
Hansen Solubility Parameters for solvent selection, NASA / Cantera Species Builder for fitted thermodynamic polynomials, and VLE / Flash for mixtures.