Chemical Libraries

Open-source cheminformatics libraries for JavaScript. Isomorphic — works in Node.js and browsers.

Packages

Package	Description	npm
@chemistry/common	Common data formats and interfaces (JMol, JNMol)
@chemistry/elements	Periodic table — element properties, radii, colors
@chemistry/formula	Chemical formula parsing, stringification, molecular weight
@chemistry/math	Linear algebra — Vec3, Matrix3x3, Transform3D, Quaternion
@chemistry/molecule	Molecule data structure, JNMol loading, SVG export
@chemistry/space-groups	230 crystallographic space groups with symmetry operations

Quick Start

npm install @chemistry/elements

import { ChemElements } from '@chemistry/elements';

const hydrogen = ChemElements.getById(1);
// { id: 1, symbol: "H", RCow: 0.37, RVdW: 1.2, maxBonds: 1, mass: 1.00794, name: "Hydrogen", ... }

const carbon = ChemElements.getBySymbol('C');
// { id: 6, symbol: "C", RCow: 0.77, RVdW: 1.7, maxBonds: 4, mass: 12.0107, name: "Carbon", ... }

import { Formula } from '@chemistry/formula';

const parsed = Formula.parse('C2H5OH');
// { C: 2, H: 6, O: 1 }

const weight = Formula.convertToWeight(parsed);
// 46.069

import { SpaceGroup } from '@chemistry/space-groups';

const sg = SpaceGroup.getById(225);
// { id: 225, hm: "F m -3 m", hs: "-F 4 2 3", o: 24, s: [...192 symmetry operations] }

Tech Stack

• Monorepo: npm workspaces
• Language: TypeScript 5.9, strict mode, ESM-only
• Testing: Vitest, 70% coverage threshold
• Linting: ESLint flat config + typescript-eslint + Prettier
• CI/CD: GitHub Actions — automated weekly releases
• Target: ES2020, isomorphic (Node.js 20+ & modern browsers)

Development

npm install
npm run build
npm run verify    # type-check + lint + format:check + test + build

Commands

Command	Description
npm run verify	Full validation pipeline
npm run build	Build all packages (dependency-ordered)
npm run test	Run unit tests
npm run lint	Lint source code
npm run format	Format with Prettier
npm run format:check	Check formatting
npm run type-check	TypeScript type checking
npm run clean	Remove dist and coverage

License

MIT © Volodymyr Vreshch