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Methodology and Data Sources

This page explains which values are stored, how diagrams are rendered, when PubChem is used and where the current tool's output requires independent verification.

Current product model: a curated educational reference for supported compounds—not a universal first-principles Lewis structure solver.

1. Supported local compound records

For a local match, the JavaScript database supplies the compound name, formatted formula, total valence-electron count, net charge, central atom, geometry, approximate bond angle, hybridization label, molar mass, elemental composition and a rendering key.

The browser renderer uses the record and rendering key to construct the displayed SVG-style diagram. These values are not derived from arbitrary user input at runtime.

2. Input normalization and aliases

Local lookup trims the input, converts it to uppercase and removes spaces. Selected common names and condensed formulas map to database keys through an alias table. Charged notation must match a supported key or alias.

Shareable URLs use the ?formula= parameter, for example /?formula=CO2.

3. PubChem fallback

If no local match exists, the page may query the public PubChem PUG REST service by compound name or molecular formula. When a match is found, the tool displays PubChem's conventional two-dimensional structure and links to the corresponding CID.

PubChem fallback is not equivalent to a Lewis dot result. It can omit electron dots, lone pairs, complete formal-charge reasoning, resonance contributors, VSEPR explanations and local property fields.

4. Molecular properties

For local records, geometry, bond angles, hybridization and molar mass are stored educational reference values. They may represent an introductory model rather than a complete quantum-chemical treatment. Unsupported PubChem property fields are intentionally shown as unavailable.

5. Educational guide pages

The molecule and topic pages are written separately from the generator database. They explain electron counting, bond placement, lone pairs, formal charges, resonance and VSEPR reasoning. They are not generated by replacing a formula in one generic template.

6. Validation and corrections

Records and educational explanations should be checked against standard general-chemistry references before publication. Representations can depend on resonance convention, charge state, protonation, instructional level and whether an expanded-valence model is permitted.

To report an issue, use the contact page and include the formula, displayed result, expected correction and supporting explanation.

7. Change policy

Do not claim universal molecule support.
Do not publish unverifiable ratings, user counts, accuracy percentages or institutional endorsements.
Label PubChem results as conventional 2D references.
Document product limitations close to the result.
Add new molecule pages only when they provide compound-specific educational value.

Last reviewed: July 15, 2026.