Archetypal energy landscapes: dynamical diagnosis

Area of Science:

• Physical Chemistry
• Computational Chemistry
• Chemical Dynamics

Background:

• Potential energy surfaces (PES) govern molecular dynamics and thermodynamics.
• Distinct PES topographies, termed "palm tree," "willow tree," and "banyan tree" motifs, correlate with unique dynamic behaviors.
• Understanding these motifs is crucial for predicting system properties.

Purpose of the Study:

• To quantitatively analyze the relationship between PES topography and dynamics for identified motifs.
• To determine the key factors influencing kinetic properties in different PES topographical patterns.
• To provide insights for distinguishing between structure-seeking and glass-forming systems.

Main Methods:

• Analysis of disconnectivity graphs representing PES topography.
• Quantitative assessment of stationary point arrangements relative to the global minimum.
• Evaluation of energy barriers for inter-basin transitions and local minima.

Main Results:

• For "palm tree" and "willow tree" motifs, stationary point arrangement in monotonic sequences dictates kinetics.
• "Banyan tree" motifs, characterized by rough surfaces and deep basins, show kinetics dominated by escape barriers relative to intra-basin barriers.
• Kinetic properties are strongly dependent on the specific PES topography.

Conclusions:

• The topographical features of potential energy surfaces significantly influence system dynamics.
• Different motifs require distinct analyses to understand their kinetic behavior.
• This work aids in differentiating the dynamics of structure-seeking versus glass-forming systems based on PES analysis.