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σ-profiles, explained

Practical, no-hype guides to σ-profiles, COSMO-RS, solubility prediction, and reproducible computational chemistry — written for the people who use these numbers to make decisions.

reproducibilityprovenance8 min read

Audit-grade computational chemistry: provenance, reproducibility, and trust

A computed result you cannot reproduce or defend is a liability. What makes a σ-profile audit-grade — pinned recipes, provenance, and tamper-evidence.

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hydrogen-bondingsigma-profile7 min read

Hydrogen-bond donors and acceptors, straight from the σ-profile

The wings of a σ-profile encode H-bond donor and acceptor capacity. How the donor/acceptor split is computed and why it matters for solubility and partitioning.

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DFTmethodology9 min read

Choosing a DFT recipe for σ-profiles: functional, basis, and cavity

The three knobs that decide σ-profile quality — functional, basis set, cavity — and why a fixed, validated recipe beats ad-hoc choices.

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sigma-momentsQSPR7 min read

σ-moments: compressing a σ-profile into features that predict

σ-moments turn the full σ-profile into a handful of numbers you can drop into a model. What each moment means and how to use them responsibly.

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solubilityCOSMO-RS8 min read

Predicting solubility from σ-profiles: what works and what doesn't

Solubility is activity coefficient times a melting term. Here's how σ-profiles give you the first half rigorously — and how to handle the second half honestly.

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COSMO-RSthermodynamics10 min read

COSMO-RS explained, without the heavy math

COSMO-RS predicts liquid-phase thermodynamics from σ-profiles. A plain-language tour of the model, what it's good at, and where its limits are.

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sigma-profileworkflow9 min read

From SMILES to σ-profile: the full pipeline, step by step

What actually happens between typing a SMILES string and getting a σ-profile: 3D embedding, conformers, DFT, COSMO solvation, and surface integration.

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sigma-profileCOSMO-RS8 min read

What is a σ-profile? A practical guide for formulation and process chemists

A σ-profile is the fingerprint of how charge sits on a molecule's surface. Here's what it is, how to read one, and why it predicts solubility and partitioning.

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Ready to generate one?

Paste a SMILES and get a σ-profile back — free converter for triage, reference-grade with signed provenance when it has to be defensible.