From classical to quantum and back: Hamiltonian adaptive resolution path integral, ring polymer, and centroid...

Area of Science:

• Computational physics
• Quantum chemistry
• Molecular dynamics

Background:

• Path integral methods are essential for simulating nuclear quantum effects but are computationally expensive.
• Existing classical simulations do not capture crucial quantum phenomena.

Purpose of the Study:

• To develop a computationally efficient multiresolution method for path integral simulations.
• To integrate this method with advanced path integral techniques like path-integral molecular dynamics, ring-polymer molecular dynamics, and centroid molecular dynamics.

Main Methods:

• A multiresolution approach restricting quantum treatment to a localized region within a classical reservoir.
• Development of a new integration algorithm incorporating multiple time-stepping.
• Validation using adaptive classical-path-integral simulations of liquid water.

Main Results:

• The proposed method successfully extends existing path integral simulation techniques.
• The integration algorithm with multiple time-stepping enhances efficiency.
• The approach is validated for liquid water simulations.

Conclusions:

• The multiresolution path integral method offers a significant reduction in computational effort for quantum simulations.
• This technique has broad applicability for simulating interfaces and complex biomolecular systems.
• Enables more efficient investigation of nuclear quantum effects in diverse systems.