The Minimal-Basis Run Gave T4-Lysozyme the Wrong Binding Sign: What Cleveland Clinic, RIKEN and IBM Changed to Correct It

Quentir Medicine Monitor

Evidence-based insights for quantum medicine.

On 9 September 2026 Cleveland Clinic announced that a team from Cleveland Clinic, the RIKEN Center for Computational Science and IBM had reached the finals of the 2026 ACM Gordon Bell Prize, for quantum-classical electronic-structure calculations on protein-ligand complexes of 11,608 and 12,635 atoms. Four days earlier the preprint behind that entry gained a second version, and buried in it is a result that deserves more attention than the atom count.

When the team computed the binding energy of a well-studied protein-ligand pair in a minimal basis set, the answer came out too positive, which is to say it pointed the wrong way for a ligand known to bind. Recomputing it with richer orbitals in the binding region and a tighter bath threshold together corrects the sign of the binding energy, at about ten times more in total node-hours. The revision also reports a first end-to-end wall-clock time, 62.4 hours from fragment generation to energy reconstruction, for a bound-complex ground-state run.