CB[5]@CB[10]. Dynamics and Interaction Energy Considerations in a Molecular Gyroscope from MD+EDA Calculations
Margot Paco-Chipana1, Alvaro Muñoz-Castro2
1Doctorado en Biología Computacional, Facultad de Ingeniería, Universidad San Sebastián, Bellavista 7, Santiago 8420524, Chile.
The Journal of Physical Chemistry. A
|May 27, 2026
Summary
Supramolecular gyroscane complexes exhibit dynamic motions, with noncoaxial conformations being energetically favored. Chloride inclusion enhances molecular motion by modulating electrostatic interactions, advancing molecular machine design.
Area of Science:
- Supramolecular Chemistry
- Nanotechnology
- Computational Chemistry
Background:
- Supramolecular noncovalent interactions are crucial for developing flexible molecular machinery.
- Understanding the dynamics of nanoscale molecular machines is essential for their functional applications.
Purpose of the Study:
- To evaluate the dynamical behavior of supramolecular gyroscane-like complexes (CB[5]@CB[10] and Cl@CB[5]@CB[10]-).
- To elucidate the impact of anion incorporation on supramolecular interaction dynamics.
- To provide insights for designing controllable, multifunctional artificial molecular machines.
Main Methods:
- Combined molecular dynamics (MD) simulations and energy decomposition analysis (EDA), termed the MD+EDA approach.
- Analysis of energetic contributions and conformational preferences.
Main Results:
- Noncoaxial conformations are energetically favored due to reduced Pauli repulsion and enhanced electrostatic interactions.
- Intricate gyroscope-like rotational and precessional motions were revealed between the inner CB[5] and outer CB[10] units.
- Chloride inclusion was found to buffer electrostatic stabilization, facilitating freer molecular motion.
Conclusions:
- The MD+EDA approach effectively elucidates the dynamics of supramolecular complexes.
- Anion incorporation significantly modulates supramolecular interaction dynamics and molecular motion.
- Findings advance the understanding of noncovalent interactions in dynamic supramolecular assemblies for molecular machine design.
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