Implicit Solvent Sample-Based Quantum Diagonalization

Area of Science:

• Quantum computing
• Computational chemistry
• Electronic structure theory

Background:

• The sample-based quantum diagonalization (SQD) method is promising for quantum-centric simulations of molecular ground state energies.
• Accurately simulating electronic structure requires including solute-solvent interactions, crucial for biochemical and medical applications.
• Previous SQD applications were limited to gas-phase simulations, lacking solvent effects.

Purpose of the Study:

• To bridge the gap in SQD applications by incorporating solvent effects.
• To introduce the integral equation formalism polarizable continuum model (IEF-PCM) into SQD calculations.
• To demonstrate the feasibility of SQD with IEF-PCM for solvated molecular systems.

Main Methods:

• Performed SQD/cc-pVDZ IEF-PCM simulations on methanol, methylamine, ethanol, and water in aqueous solution.
• Utilized quantum hardware (ibm_cleveland, ibm_kyiv, ibm_marrakesh) with varying numbers of qubits (27, 30, 41, 52).
• Compared results with traditional CASCI/cc-pVDZ IEF-PCM simulations.

Main Results:

• Successfully integrated IEF-PCM solvent model into SQD calculations.
• Obtained ground state energies for small molecules in aqueous solution using quantum hardware.
• Demonstrated the scalability of the SQD IEF-PCM method with increasing qubit counts.

Conclusions:

• The SQD IEF-PCM method is a viable approach for quantum simulations of molecules in solution.
• This work extends the applicability of SQD to chemically relevant condensed-phase systems.
• The demonstrated scalability suggests potential for larger, more complex molecular simulations on quantum computers.