A team from Cleveland Clinic, RIKEN, and IBM used two IBM quantum computers and two supercomputers to model biologically relevant molecules at scale. The researchers employed a quantum-centric supercomputing workflow to simulate protein–ligand chemistry, with the largest simulation reaching over 12,000 atoms (30,000 orbitals). The work modeled the proteins T4-Lysozyme and Trypsin in solution with binding agents. The simulation scale reached 12,635 atoms, representing a significant advancement in quantum chemistry research. The team simulated these proteins binding to molecules they interact with in nature and immersed in a liquid water solution, at scales of 11,608 atoms and 12,635 atoms respectively. Bringing together an international team of researchers from across the United States and Japan made it possible to develop the necessary algorithm and workflow enhancements to reach this milestone. The researchers achieved this scale just four months after modeling the 303-atom miniprotein Trp-cage using quantum computing for the first time. Today’s new result not only demonstrates a 40-fold increase in system size compared to the Trp-cage result, it represents a 210-times improvement in accuracy from previous state-of-the-art QCSC approaches in a specific step of the workflow. To reach these new heights of scale and accuracy, the researchers refined both classical and quantum methods used in the workflow. They performed quantum sampling on two 156-qubit IBM Quantum Heron r2 processors, and then processed the resulting data using the classical supercomputers Fugaku and Miyabi-G. High-performance computing experts from RIKEN joined the team and played a key role in the work. *Source: [ibm](https://research.ibm.com/blog/cleveland-clinic-riken-chemistry)*