Issues

• PM6_SP with analytical_gradient=True silently returns wrong forces for F-containing molecules

  lanl/PYSEQM#18 · Filter by author xlalxxlilx opened on Oct 19, 2026

• Forces (and the local energy surface) are wrong when an atom-pair vector is anti-parallel to the x axis (rotate_with_quaternion)

  lanl/PYSEQM#17 · Filter by author xlalxxlilx opened on Oct 19, 2026

• diatom_overlap_matrixD: wrong overlaps for several (n, l) combinations and an orientation-dependent d–d block

  lanl/PYSEQM#16 · Filter by author xlalxxlilx opened on Oct 19, 2026

• Bundled PM6 parameters: no values for 4d/5d transition metals; other values rounded

  lanl/PYSEQM#15 · Filter by author xlalxxlilx opened on Oct 19, 2026

• Constants tables are misaligned for Z ≥ 57 (Hf and heavier elements cannot be used)

  lanl/PYSEQM#14 · Filter by author xlalxxlilx opened on Oct 19, 2026

• Is phosphorus supported?

  lanl/PYSEQM#9 · Filter by author tkramer-motion opened on May 11, 2025
  1

• AM1 parameters are incomplete

  lanl/PYSEQM#4 · Filter by author thegodone opened on May 31, 2022
  1

• how to compute the partial charges of atoms ?

  lanl/PYSEQM#3 · Filter by author thegodone opened on May 30, 2022
  1