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Updated: Jun 23, 2026
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Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Quantum disordering versus melting in Lennard-Jones clusters
Jason Deckman1, Vladimir A Mandelshtam
1Department of Chemistry, University of California at Irvine, Irvine, California 92697, USA.
Summary
Quantum delocalization length influences Lennard-Jones cluster structures. Longer lengths favor disordered, liquidlike states over compact ones, revealing similarities between quantum and thermal transitions.
Area of Science:
- Physical Chemistry
- Computational Chemistry
- Quantum Mechanics
Background:
- Lennard-Jones clusters exhibit diverse structural motifs.
- Quantum effects can significantly alter cluster properties at low temperatures.
Purpose of the Study:
- To construct a phase diagram for Lennard-Jones clusters based on quantum delocalization.
- To investigate the influence of quantum delocalization on cluster structure and energetics.
- To explore analogies between quantum and thermal structural transitions.
Main Methods:
- Estimation of ground states for Lennard-Jones clusters (n=147).
- Systematic variation of de Boer quantum delocalization length (Lambda).
- Construction of the n-Lambda phase diagram.
Main Results:
- The de Boer quantum delocalization length (Lambda) was correlated with cluster size (n).
- Increased Lambda favors disordered, diffuse structures over symmetric, compact ones.
- Liquidlike motifs become energetically favorable at larger Lambda values.
Conclusions:
- Quantum delocalization is a key parameter in determining Lennard-Jones cluster ground states.
- A direct analogy exists between quantum-induced and thermally-induced structural transitions.
- The n-Lambda phase diagram provides insights into quantum-classical transitions in clusters.
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