Fast time-reversible algorithms for molecular dynamics of rigid-body systems

Area of Science:

• Computational Physics
• Molecular Dynamics
• Numerical Methods

Background:

• Rigid body simulations are crucial in various scientific fields.
• Existing time-reversible algorithms often require iterative calculations for angular velocity, impacting efficiency.
• Quaternion representation offers advantages for describing molecular rotations.

Purpose of the Study:

• To develop novel, iteration-free, time-reversible simulation algorithms for rigid bodies.
• To enhance the computational speed and efficiency of molecular dynamics simulations.
• To evaluate the stability of total energy and computational performance compared to existing methods.

Main Methods:

• Proposed two new iteration-free algorithms based on advancing a previously established time-reversible method.
• Implemented these algorithms in code for practical application.
• Conducted comparative simulations using a nanometer-sized water droplet model.

Main Results:

• The new algorithms demonstrate improved computational speeds.
• The proposed methods maintain stability in total energy during simulations.
• Iteration-free approach significantly reduces computational overhead.

Conclusions:

• The developed iteration-free algorithms offer a faster and efficient alternative for time-reversible rigid body simulations.
• These algorithms are easily implementable in existing simulation codes.
• The findings are validated through simulations of a water droplet, showing good energy conservation and speed.