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Updated: Jul 3, 2026
10:37
Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Quantum transitions in Lennard-Jones clusters.
Jason Deckman1, Pavel A Frantsuzov, Vladimir A Mandelshtam
1Chemistry Department, University of California at Irvine, Irvine, California 92697, USA.
Summary
Quantum effects influence the structure of Lennard-Jones clusters. Increasing quantum delocalization length (Lambda) can induce transformations between Mackay and anti-Mackay icosahedral structures.
Area of Science:
- Computational physics
- Quantum chemistry
- Materials science
Background:
- Lennard-Jones (LJ) clusters are model systems for studying the behavior of atoms and molecules.
- Understanding the ground states and structural transformations of these clusters is crucial for predicting material properties.
Purpose of the Study:
- To estimate the ground states of Lennard-Jones clusters using quantum mechanical principles.
- To construct a phase diagram exploring the interplay between cluster size and quantum delocalization.
- To identify the stability regions of different structural motifs, specifically Mackay and anti-Mackay icosahedra.
Main Methods:
- Minimization of the energy functional using Gaussian wave packets.
- Construction of a phase diagram for LJ clusters (n=31-45) as a function of de Boer quantum delocalization length (Lambda).
Main Results:
- The study reveals distinct stability ranges for Mackay and anti-Mackay icosahedral structures within the explored phase space.
- A correlation is established between increased quantum delocalization length (Lambda) and structural transformations.
- The effect of increasing Lambda is analogous to thermal heating, potentially inducing phase transitions.
Conclusions:
- Quantum delocalization is a significant factor governing the structural stability of Lennard-Jones clusters.
- The phase diagram provides insights into the quantum-classical transition in these systems.
- Further investigation into the role of quantum effects in cluster dynamics is warranted.
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