CogLabThe Cognition Lab

Physics simulations

The physics workbench

See how a crystal responds.

Explore the energy landscape of four metals. Inspect every calculated point, understand the model behind it, and run your own volume scans.

Aluminum · reference calculation

Energy & volume

Calculated · EMT · 0 K

Compress or expand an ideal crystal. The energy minimum estimates its preferred volume; the curvature measures resistance to compression.

Lattice parameter3.994 ÅConventional FCC unit cell
Equilibrium volume15.93 ų/atomFitted energy minimum
Bulk modulus39.6 GPaModel estimate at 0 K
Energy relative to the fitted minimum in millielectronvolts per atom versus volume in cubic ångströms per atom. Dots are computed samples; connecting lines are a visual guide. Tab to a point and use the arrow keys to inspect adjacent samples. Home and End select the first and last sample. Exact values follow in the data table.Relative energy (meV/atom)Volume (ų/atom)
Computed samplesFitted equilibrium volume
Lines between samples guide the eye. Energy is relative to the fitted minimum, not an isolated-atom reference.
Sample 7 of 1316.6075 ų/atom3.38129 meV/atom relative to fitted minimum
Inspect the 13 computed samples
Absolute energies use the EMT potential’s energy reference.
SampleVolume (ų/atom)Energy (eV/atom)Relative energy (meV/atom)
115.27892875-0.00143287623.45045960
215.50036250-0.00339551821.48781760
315.72179625-0.00453601660.34731919
415.94323000-0.00488159490.00174086
516.16466375-0.00446661560.41672015
616.38609750-0.00332783101.55550482
716.60753125-0.00150204763.38128821
816.828965000.00097500925.85834500
917.050398750.00406926098.95259670
1017.271832500.007748597112.63193292
1117.493266250.011983131616.86646742
1217.714700000.016745508421.62884420
1317.936133750.022011355126.89469089
Method, numerical checks & provenance

ASE’s effective-medium theory potential evaluates an ideal face-centered cubic crystal at 0 K. A stabilized jellium equation of state fits 13 volumes over ±8%. The fit residual is 0.0000051321 eV/atom. It measures fit error, not uncertainty against experiment.

Energy minimum
Inside sampled range · positive curvature
Energy–stress consistency
2.132e-11 ≤ 0.00001 eV/ų
Finite-difference force check
4.132e-10 ≤ 0.0001 eV/Å
Supercell energy agreement
5.662e-15 ≤ 1e-7 eV/atom
Engine
ASE 3.29.0 · NumPy 2.5.4 · SciPy 1.18.1
Calculated
Input SHA-256
d3a90e940a55a44a9f4c811cf7ef6a5cc9ad84b968ff1bac23d97972e428e568
Worker SHA-256
4c14dfddcb3696be2ad35f0a4fb02ef0ba2716d654f3d571b6a2f883cd78e47c

These checks establish numerical consistency within this model. Experimental accuracy and property uncertainty have not been quantified for this run.

Read the EMT method ↗