ECCE 9.0.0

ECCE 9.0.0, the first release of the 9 series. 8.18.x continues with bug fixes only. 9.x does not interoperate with 8.x; see Upgrading from 8.x. Please report problems as issues.

Platforms. Linux (Debian 13 tested; Ubuntu 24.04, RHEL/Rocky 9 and Fedora packages are built on those systems but not tested). Windows 10 (tested) and 11. macOS, Apple silicon and Intel: experimental, built but not tested for this release.

What 9.0 brings, compared with 8.18

• Runs on your own computer without a server: "Store data on this computer" keeps projects in a local folder; a central data server for a group or a class remains fully supported, with HTTPS and MQTT over TLS (ecce-remote-setup --tls).
• Windows and macOS clients, next to Linux.
• ECCE-QM, a built-in Hartree–Fock/DFT program that needs nothing else installed: energies, geometry optimisation, frequencies with IR intensities and thermochemistry, orbitals, Mulliken, Löwdin, CHELPG and Merz–Kollman charges. Checked against ORCA 6.1.1.
• Two packages, ecce-client and ecce-server; Mosquitto replaces ActiveMQ and Java.
• Jobs run without an interactive shell: commands run directly on this machine and over ssh elsewhere; job scripts are POSIX sh. A job is shown as killed only when you cancel it from ECCE. HTCondor is supported as a queue manager.
• Job progress in the Organizer: SCF, optimisation and frequency progress with plots, for ECCE-QM, ORCA, Gaussian, NWChem, MOPAC, Quantum ESPRESSO and GROMACS; a job out of contact is shown as "running?", not as failed.
• Results: MO composition; partial charges from every scheme the codes provide; thermochemistry and solvation terms; the spectrum viewer; ESP surfaces about 30 times faster, with a colour bar; the polarizability as an ellipsoid.
• The 3-D viewer on Coin3D, with accurate transparency, smoother atoms and per-pixel lighting; Jmol element colours by default.
• Register Machines as a tabbed editor with queue discovery and a job-script preview.
• An MO correlation diagram (experimental): for small molecules, from fragment orbitals; check it against the MO list.
• Help inside ECCE, including installing codes on Linux, Windows and macOS, and video tutorials.

Changes since 9.0.0-beta.2

Partial charges (#272)

• Gaussian 16: Theory Details requests Hirshfeld (with CM5) and ESP-fitted charges (Merz–Kollman or CHelpG) together with NBO, in one Pop= keyword; AIM (Bader) charges are read.
• ORCA: Runtype Details requests Hirshfeld, MBIS and NBO (natural) charges besides CHELPG; Mulliken and Löwdin come with every job.
• ECCE-QM: Löwdin, CHELPG and Merz–Kollman charges. Compared with ORCA on H2O, NH3, CO and HF (HF and B3LYP/6-31G*): Löwdin within 0.00001 e, CHELPG within 0.005 e.
• NWChem and MOPAC: ESP-fitted charges from a tick box in Theory Details (NWChem's esp module, MOPAC's ESP keyword).
• NBO: Gaussian 16's Theory Details chooses NBO 7 or NBO 6 (G16 C.01 and later use NBO 7).

ECCE-QM

• Faster: integral screening and a pruned DFT grid make DFT runs 2 to 3.4 times faster (caffeine B3LYP/6-31G* energy: 188 s → 54 s); results unchanged to 3e-9 Eh and 0.00 cm⁻¹.
• The MO diagram is offered by default for ECCE-QM calculations (Preferences › Molecular orbitals turns it off).
• Help: an ECCE-QM page, and every input keyword documented.

Organizer and Launcher

• A finished job keeps its Progress plots, with the outcome below them (#284).
• Ctrl+click adds a calculation to the selection (#290).
• "Local data" cannot be cut, renamed or deleted; deleting it crashed ECCE (#288).
• Memory Limit and Scratch Space show their unit in the Launcher (#289).
• No crash on exit when the Organizer's close button is pressed twice (#291).

Viewer and Builder

• A window tiled to half the screen keeps its size instead of hopping (#275).
• MO panel with an ESP or density surface: the table keeps its place (#285).
• Element tool: a click adds atoms with the current element; the ▾ next to it, or a right-click, opens the periodic table below the button (#286).
• MO diagram: for C2 and N2 the 3σg level is linked to both 2s and 2p (s–p mixing, #287).
• No GTK size warning when opening MD Optimize.
• Memory errors fixed in the viewer's surface nodes and in counting basis functions for very high angular momentum.

New

• Example calculations: File › Open Example Calculations imports four finished calculations into a new project: water with ECCE-QM, benzene with ORCA (including NBO), ammonia with MOPAC and methane with NWChem.
• Dummy atoms (#298): the Builder's dummy atom X has no electrons and needs no basis set. NWChem and ORCA write it in their own syntax (X, DA) and keep constraints that refer to it; Gaussian 16 runs with dummy atoms and renumbers constraints around them (a constraint that names the dummy itself is not supported and Verify warns); MOPAC writes XX; ECCE-QM refuses dummy atoms with a message.
• ORCA geometry constraints (fixed atoms, bonds, angles, torsions) are now written to the input; they were ignored before.
• MOPAC outputs can be imported.
• A Ligands folder in the Structure Library: PPh3, PMe3, CO, CN⁻, NH3, H2O, pyridine, bipyridine, phenanthroline, ethylenediamine, acac⁻, Cp⁻ and oxalate, each attaching to a metal at its donor atom.
• Progress for older calculations: a finished calculation without a Progress record gets one, built once from its stored output.
• First start with a server on this computer: when "Connect to a server" uses this computer's own data server and no account exists, the login window offers to create it (#203).
• Details dialogs in C++ (preview): ECCE-QM's Theory Details as a native dialog, used only with ECCE_NATIVE_DIALOGS=1; the Python dialog remains the default.

Builder and Calculation Editor

• Save is enabled as soon as the structure changes, and Ctrl+S, Ctrl+N, Ctrl+O, Ctrl+W and the selection shortcuts work while the 3-D view has the focus.
• The Geometry Constraints dialog shows every column of its tables.
• The Open structures pane is only as tall as its list; the empty "Unnamed1" structure no longer appears next to a calculation's structure.
• Verify knows every ECCE-QM input keyword.

Preferences

• An Advanced tab with switches for testing and troubleshooting (C++ Details dialogs, per-pixel lighting, progress records for older calculations, diagnostic logs), for systems where ECCE is not started from a terminal (#307).

Windows

• Importing calculations works (including File › Open Example Calculations): the importer looked the computer up under its host name, while Windows registers it as localhost.
• The Launcher shows its units (GB, MB) (#289).
• The Start menu entry and the taskbar show the current ECCE icon (#292).
• Selecting calculations in the project table no longer redraws the whole window (#296).
• Choosing HF in the Calculation Editor no longer leaves a second row of buttons (#294).
• The MO diagram finds its symmetry operations reliably (#295).

Administrators

• ECCE_HIDE_MO_DIAGRAM yes in siteconfig/site_runtime hides the MO diagram for every code on an installation (#280).

Help

• Running codes on Linux: NWChem, MOPAC, GROMACS, Quantum ESPRESSO and CP2K from the distribution; ORCA from FACCTS (https://www.faccts.de/orca/; Debian's orca package is a screen reader); Gaussian; NBO.

Known issues

• GROMACS (experimental) does not yet handle periodic molecules such as clay sheets (#262) or force-field folders (#260).
• The Build pane cannot be made taller than the other panes in its column allow (#293).
• The MO diagram is experimental; it can be incomplete for larger molecules.

Packages

System	Files
Debian 13	ecce-client_9.0.0_amd64.deb, ecce-server_9.0.0_amd64.deb
Ubuntu 24.04	ecce-client_9.0.0_ubuntu24.04_amd64.deb, ecce-server_9.0.0_ubuntu24.04_amd64.deb
RHEL/Rocky 9	ecce-client-9.0.0-1.el9.x86_64.rpm, ecce-server-9.0.0-1.el9.x86_64.rpm
Fedora	ecce-client-9.0.0-1.fedora.x86_64.rpm, ecce-server-9.0.0-1.fedora.x86_64.rpm
macOS 11 or newer (experimental)	ECCE-9.0.0-arm64.dmg (Apple silicon), ECCE-9.0.0-x86_64.dmg (Intel)
Windows 10/11	ECCE-windows-9.0.0.msi (installer) or ECCE-windows-9.0.0.zip

Installation: Installing ECCE. Videos: Your first calculation with ECCE-QM, Your first ORCA calculation with ECCE.