Rowan Docs

Running Rowan's LogP Prediction Workflow

Rowan's logP workflow predicts the neutral compound's base-10 octanol–water partition coefficient using a Chemprop model, the RDKit Crippen model, or COSMO-RS. See the logP science page for the methods and equations behind each option.

To begin, open Rowan's workflow picker and select LogP prediction.

Select a molecule

LogP predictions accept one molecule. The workflow predicts logP for the neutral compound, so check the input's protonation state and use a neutral representation rather than a salt or disconnected mixture.

To add a molecule, you can use any of the following input formats:

  • Draw a molecule using Rowan's 2D or 3D editors.
  • Upload a file, using the "Upload files" button. (Rowan accepts .xyz, .gjf, .out, .mol2, .sdf, .cif, and .mae chemical file formats.)
  • Paste XYZ coordinates, using the "Paste XYZ" button.
  • Input a SMILES string, using the "Input SMILES" button.
  • Input the name of the chemical, for its information to be fetched from PubChem.
  • Drag and drop files anywhere on the page.

For small molecules, it's often easiest to start with a SMILES string. Many 2D molecule drawing programs, including ChemDraw and MarvinJS, will let you export/copy structures as SMILES.

Editing structures

To modify a structure you have already entered, click the pencil icon in the top-right corner of the molecule viewer and use Rowan's 3D editor.

Choose a method

  • Chemprop Sangster2026 is the default and is a good choice for most screening and property-prediction tasks.
  • Crippen is an effectively instantaneous 2D fragment model. Use it for a quick baseline or very large screens.
  • COSMO-RS performs conformer sampling and physics-based solvation calculations. It is substantially slower and more expensive, but it accounts explicitly for conformational and solvent effects.

Submit and interpret the result

Click Submit logP to start the workflow. The result is a single logP value: larger positive values indicate a greater preference for octanol, while smaller or negative values indicate a greater preference for water.

Compare values only for chemically meaningful neutral forms. If ionization at a particular pH matters, logD rather than logP is the relevant experimental quantity.