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Mode selectivity of dynamically induced conformation in many-body chainlike bead-spring models
1Graduate School of Informatics, Kyoto University, Kyoto 606-8501, Japan.
Physical Review. E
|July 19, 2023
Summary
Dynamically induced conformations in bead-spring chains are stabilized by specific spring motions. Lower frequency modes stabilize, while higher frequencies destabilize chain structures, confirmed by simulations.
Area of Science:
- Physics
- Polymer Physics
- Statistical Mechanics
Background:
- Conformation of bead-spring chains is governed by bending angles and potential energy.
- Excited spring forces can alter conformational stability, leading to unusual states.
- Previous work identified dynamically induced conformations in three-body systems.
Purpose of the Study:
- Extend the analysis of dynamically induced conformations to many-body chainlike bead-spring systems.
- Investigate the influence of excited normal modes on chain conformation stability.
- Establish general rules for stabilization/destabilization based on eigenfrequencies.
Main Methods:
- Theoretical analysis of bead-spring chain dynamics.
- Investigation of normal modes and their dependence on conformation.
- Numerical simulations to verify theoretical predictions.
Main Results:
- The lowest-eigenfrequency normal mode generally contributes to conformational stabilization.
- Higher eigenfrequencies of excited modes tend to destabilize the conformation.
- A conformation can be stabilized near potential energy maxima or saddle points.
Conclusions:
- Dynamically induced conformations are a general phenomenon in many-body bead-spring systems.
- Conformational stability is intricately linked to the interplay between potential energy and excited normal modes.
- Simple rules governing stabilization and destabilization based on eigenfrequencies are identified.
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