The Extensible Computational Chemistry Environment (ECCE, pronounced "etch-ā"; ecce is Latin for "behold") is a graphical environment for computational chemistry: build a molecule, set up a calculation, run it on your own computer or a cluster, and look at the results (orbitals, densities, vibrations, geometry optimisations), with every calculation kept in one place.
It works with NWChem, Gaussian, ORCA and MOPAC; ECCE 9 also includes ECCE-QM, a small built-in Hartree–Fock/DFT program that needs nothing else installed. ECCE was developed at Pacific Northwest National Laboratory, which stopped supporting it around 2017; it is maintained here since, with PNNL's blessing.
More pictures and the full feature list: ECCE overview.
Download from the releases page.
- ECCE 9 (latest 9.2.2), for Linux, macOS and Windows: the recommended version. The macOS and Windows clients are experimental.
- ECCE 8.18.x (latest 8.18.12), Linux only: the older line, which still gets bug fixes.
| System | File | Install |
|---|---|---|
| Debian 13, Ubuntu 24.04 | ecce-client_…deb, ecce-server_…deb |
sudo apt install ./ecce-client_*.deb ./ecce-server_*.deb |
| RHEL/Rocky 9, Fedora | ecce-client-…rpm, ecce-server-…rpm |
sudo dnf install ./ecce-*.rpm (on RHEL/Rocky first sudo dnf install epel-release) |
| macOS | ECCE-…-arm64.dmg (Apple silicon) or …-x86_64.dmg (Intel) |
open it and drag ECCE to Applications; macOS refuses it at first: on macOS 15 and later open it once, then System Settings → Privacy & Security → Open Anyway (macOS 14 and earlier: right-click → Open), or run xattr -dr com.apple.quarantine /Applications/ECCE.app |
| Windows 10/11 | ECCE-windows-….msi |
double-click; at the SmartScreen warning choose More info → Run anyway |
Then start ecce (on macOS and Windows: ECCE in Applications or the
Start menu). Details for each system: Installing ECCE.
Planned, being worked on:
- GROMACS from start to finish: preparing proteins (
pdb2gmx), clay and mineral systems (MINFF) and small molecules (AmberTools), and results shown as plots and trajectories (#262, #334, #336). - A finished job's orbitals as the starting guess of the next calculation, ORCA first (#75).
- Quantum ESPRESSO: a full Verify and automatic choice of k-points and cutoff (#349).
- Windows that fit small screens: the QE Theory Details, the plot panels and the Basis Set Tool (#337, #351).
- Calculation Editor: no Basis Set box for MOPAC and Quantum ESPRESSO (#348).
The same pages are in ECCE under Help. To see it done first, the chem4eva YouTube channel has short videos with subtitles: installing ECCE, a first calculation with ECCE-QM (nothing else to install) and a first ORCA calculation.
- Installation: what you see the first time ECCE starts, and where your work is kept.
- Your first calculation: build, run and look at a calculation.
- Running codes on Linux, on Windows or on macOS: installing NWChem, MOPAC, ORCA and the others, and telling ECCE where they are.
- Importing a structure or a calculation that ran elsewhere.
Questions, and how you use ECCE, are welcome in
Discussions.
Run the session that goes wrong with ecce --bug. When it ends, ECCE
collects its logs into ~/ecce-bug-<time>.zip (no passwords, but host
names, user names and paths). Attach that to a
new issue, with what
you did and what you expected.
- Getting started: building, packaging, a central server for a group or class, TLS, the other deployment modes, upgrading from 8.x.
- Contributing: building from source, branches and releases, the roadmap, and how to help.
- Changes: what is new in 9.0 and in 8.x, and the release history.
- The wiki: where things are in the code, and the current work plan.
- Accessibility: what ECCE does for keyboard, screen reader and low-vision use, and how to report a barrier.
Please cite the DOI for all versions, 10.5281/zenodo.23281771; each release also has its own DOI there. GitHub's "Cite this repository" button gives the reference in APA and BibTeX form.
ECCE is free software under the Educational Community License 2.0; see
LICENSE. For the use of the name, see TRADEMARKS.md.