Features
Two halves that share one data model: a simulation engine that writes and runs real ASE scripts, and a viewport where the structure they run on is built and inspected.
Single-point, geometry optimization, molecular dynamics (NVE/NVT/NPT with the complete ASE thermostat set, plus endpoint-exact simulated-annealing schedules), phonons with spglib symmetry reduction, Monte Carlo, NEB and cluster expansion.
Supercell finite differences give gₘₙᵛ(k,q), then the Eliashberg function α²F(ω), λ, and the relaxation time τ that feeds the Drude model. Both Fermi-surface δ-functions are integrated by the linear tetrahedron method, so there is no smearing parameter to converge. From the same α²F: Allen–Dynes Tc with the f₁/f₂ corrections, transport λtr and ρ(T), and a Tc-vs-μ* sweep — because μ* is empirical and Tc depends on it exponentially. Quote the range, never one value.
Thermodynamic integration along U(λ) from a reference whose free energy is known in closed form — ideal gas (Sackur–Tetrode), Einstein crystal (Frenkel–Ladd) or a Lennard-Jones fluid from the exact second-virial series, which refuses above ρ* = 0.05 rather than extrapolating a fit. Every window writes its raw ∂U/∂λ series, so the error bar is autocorrelation-corrected and propagated exactly through the quadrature. A run missing any window reports INCOMPLETE and no free energy at all — an integral over the survivors is a different integral, not a noisier one.
Effective cluster interactions fitted from a cluster-expansion design matrix by LASSO, ridge or ARD, judged on the leave-one-out CV score rather than the training residual. The fitted pair interaction feeds the Cluster Variation Method — point, pair and Kikuchi tetrahedron — whose spread is the correlation correction to the ideal −Σx ln x bound that high-entropy alloys are sold on. A four-sublattice solver locates FCC order–disorder transitions by free-energy crossing, reproducing Cu₃Au's 663 K at V₂ = 29.7 meV.
Band structures with PDOS, fatbands and first-principles irreducible-representation labels; band unfolding for supercells; linear, 2D and nonlinear optics (SHG, shift current) including the intraband Drude term for metals; G₀W₀ quasiparticle corrections (GPAW or Yambo); Wannier functions and interpolation; Fermi surfaces; topological invariants; XAS; Hubbard U by linear response; Born effective charges; Raman and IR spectra on three engines.
The Orchestration dock chains calculations into a DAG on a node-graph canvas — relax, then converge, then compute a spectrum — passing geometries and ground states between nodes, with per-node status and failure propagation.
Energy, temperature, force and pressure stream into plots as the job runs; MD trajectories stream frame-by-frame into the viewport while they are being computed. Jobs queue instead of refusing, and a process manager keeps every run's logs, metrics and artifacts one click away.
Connect over SSH and Calango stages the same script and structure, generates a SLURM/PBS/SGE wrapper, uploads, submits, polls the queue, streams remote logs and downloads results automatically when the job finishes.
Instanced rendering keeps tens of thousands of atoms fluid, and everything on screen is publication-ready.
Ball-and-stick, space-filling, wireframe; colouring by element (CPK), coordination number, generalized coordination number or any per-atom scalar field, through ten scientific colormaps with live legends. Gradient bond colouring, force and velocity arrows, magnetic-moment overlays.
Up to four directional Blinn-Phong lights with a three-light studio default, screen-space ambient occlusion, depth of field and distance fog — all tuned live.
Six mouse modes (rotate, pan, select, insert, distance, angle) with single-key shortcuts; ray-cast picking, rubber-band selection, snapshot undo/redo, an interactive bond editor with trajectory-wide rules, and a periodic-table element picker.
Surface slabs with an interactive Miller-index canvas; liquid/gas interfaces and ionic solutions packed to a target density; dislocations (edge, screw, dipoles, anisotropic Stroh); stacking faults, twins, bicrystals and Voronoi polycrystals; nanotubes, nanoribbons, TMD monolayers and graphene oxide; Wulff-shape nanoparticles; special quasirandom structures; polymers, water/ice and adsorbate coverages.
Isosurfaces, slice planes and dual-field potential maps from `.cube`, CHGCAR/LOCPOT/PARCHG/ELFCAR and `.xsf` grids, with OBJ mesh export.
An interactive Brillouin-zone viewer with click-to-build k-paths, exportable to VASP, Quantum ESPRESSO, CASTEP, SIESTA or an ASE script.
Off-screen renders up to 8192 px with transparency, turntable and trajectory animations (MP4/GIF and more), POV-Ray and Tachyon ray-traced scenes matching the live viewport, and Alembic export for Blender, Houdini and Maya.
Every format ASE reads and writes — CIF, POSCAR, extended XYZ, Quantum ESPRESSO, LAMMPS, Gaussian, SHELX and more — plus `.calproj` project files that restore a whole multi-tab session.
Post-processing that runs on the structure or trajectory already loaded — no export, no second tool.
Simulations never run inside the GUI process: local jobs are isolated QProcess subprocesses and remote I/O lives in a paramiko helper process, so a crashed calculation never takes the application down.