Psi4 RT-Ehrenfest driver (rtehrenfest)

Confirm prerequisites

• Ensure psi4 is installed and importable in the driver environment.
• Provide an XYZ geometry file whose second line specifies charge and multiplicity (e.g., 0 1).

Configure socket mode

• Run:

- mxldriver --model rtehrenfest --address <host> --port <port> --param "moleculexyz=../HCNbenchmark/hcn.xyz, functional=b3lyp, basis=cc-pvdz, dtrttddftau=0.04788, dftgridname=SG1, memory=2GB, numthreads=1, forcetype=ehrenfest, nfockpernuc=6, nelecper_fock=6"

Configure embedded mode

• Instantiate:

- Molecule(driver="rtehrenfest", driver_kwargs={...})

Notes

• Use forcetype=bo when nuclear gradients from Born–Oppenheimer surfaces are required; use forcetype=ehrenfest for mean-field forces.
• When passing partialcharges on the command line, use a space-separated list in brackets (no commas), e.g. partialcharges=[1.0 -1.0 0.0].
• On HPC, match numthreads to --cpus-per-task (single driver) or set numthreads=1 when launching many drivers in the same SLURM job.
• For coupled 3D plasmonic Meep + many RT-Ehrenfest drivers, prefer scaffold template: skills/mxl-project-scaffold/assets/templates/slurm-meep-plasmon-rteh-tcp.
• Read full parameter docs in docs/source/drivers/rtehrenfest.rst.