2026-06-19 MDI engines

Goal

Supporting MDI with, initially, MOPAC and xTB as engines for LAMMPS. This will allow us to use semiempirical methods with MD. This initial phase will build on the work with the MDI connections for MLFFs, starting with standalone tests and ending with incorporating the functionality in the LAMMPS step in SEAMM.

Contents:

• Development Plan: QM/MD via MDI in SEAMM — MOPAC First
  • Overview
  • Architecture
  • SEAMM integration design
  • MOPAC .mop file for MDI mode
  • Phased development plan
  • Known issues and open questions
  • Comparison with MACE MDI (for reference)
  • References
• Notes on Open Investigations: MOPAC Conda Packaging and VASP via MDI
  • Part A – mopac-feedstock conda-forge packaging
  • Part B – VASP via MDI: feasibility assessment
  • References
• Validation Notes: MOPAC Native MDI Engine for LAMMPS
  • Purpose
  • Environment and build configuration
  • Bugs identified and fixed
  • Validation results
  • Known limitations and open items
  • References
• Validation Notes: tblite MDI Engine and MOPAC Python-Wrapper MDI Engine
  • Purpose
  • Part A – tblite MDI engine
  • Part B – MOPAC Python-wrapper MDI engine (mopac_mdi.py)
  • Open items carried forward
  • References
• Scientific Finding: Semiempirical Method Accuracy for Liquid Methanol
  • Context
  • Results
  • Interpretation
  • Possible next steps (not yet pursued)
  • References