A quantum-computing chemistry workbench
Qemica is a desktop workbench designed for quantum computing — build molecules in 2D or 3D, run quantum algorithms on the local simulator or quantum hardware, and read orbitals, spectra, and dynamics back in one continuous workflow.
The workbench
Four connected stages share a single molecule, a single project, and a single design language — one continuous thread from structure to interpretation, with nothing lost in translation between tools.
Sketch a skeletal structure in the 2D editor or assemble atoms directly in the 3D viewport. SMILES in, geometry out — with a fragment and ring library for the parts you reach for most, and a force-field pre-optimization to clean up what you drew.
Pick a calculation type — optimize, frequencies, excited states, a PES scan, a transition-state search — then dial in functional, basis set, and solvent model and assign an engine and resources. Sensible defaults for every job, full control when you need it.
Jobs queue locally or on your cluster and stream their log back live. Follow SCF energy and forces step by step instead of tailing an output file in a terminal.
Orbitals and densities as isosurfaces, IR/Raman, UV-Vis and NMR as interactive spectra, geometry and thermochemistry as tables — all parsed into one consistent, comparable view, and exportable as figures and coordinates for the paper.
Quantum-ready, honestly
Electronic structure is the canonical problem for quantum computing — and the hardest part of getting there is the chemistry around the calculation: active-space selection, mapping, and reading results back into something a chemist understands. Qemica does that work today on classical hardware, behind an interface that won't change when the backend does.
When fault-tolerant VQE and quantum phase estimation become practical for real systems, they slot in as another method — your molecules, projects, and analysis stay exactly where they are.
Read the quantum roadmapDFT, HF, MP2, coupled cluster via a locally installed PySCF engine.
Active-space selection, qubit mappings, a dozen eigensolvers on the local simulator.
VQE, SQD, and the signal/Krylov methods dispatch to IBM Quantum on your account.
Free download · macOS
Qemica is free to download. The macOS build is a universal binary for Apple Silicon and Intel, signed and notarized by Apple, with a one-time guided setup of the calculation engine on first run. Windows and Linux builds are planned.
