Fundamental measure density functional theory for hard spherocylinders in static and time-dependent aligning fields
1Institut für Theoretische Physik II: Weiche Materie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, D-40225 Düsseldorf, Germany.
Summary
Fundamental measure density functional theory models hard spherocylinder dynamics. External potentials influence phase transitions, revealing a resonance in oscillating fields near the paranematic-nematic transition.
Area of Science:
- Statistical Mechanics
- Soft Matter Physics
Background:
- Fundamental measure density functional theory (FM-DFT) is a key tool for studying inhomogeneous anisotropic fluids.
- Hard spherocylinders exhibit complex phase behavior influenced by external fields.
Purpose of the Study:
- To investigate the equilibrium and dynamic phase behavior of hard spherocylinders under external orientational potentials.
- To explore the influence of a free parameter in FM-DFT on the isotropic-nematic transition.
Main Methods:
- Application of FM-DFT to model Brownian dynamics of hard spherocylinders.
- Analysis of equilibrium phase diagrams in the presence of static external potentials.
- Utilizing dynamical density functional theory for time-dependent phenomena.
Main Results:
- A phase transition from paranematic to nematic is observed for equatorial-favoring potentials, becoming second-order above a critical potential strength.
- For polar-favoring potentials, the paranematic-nematic transition disappears above a threshold.
- A resonance phenomenon is detected for oscillating external potentials near the phase transition.
Conclusions:
- The study elucidates the critical role of external potentials in controlling phase transitions in hard spherocylinder systems.
- FM-DFT provides a robust framework for understanding both equilibrium and dynamic behaviors.
- Resonances in dynamic systems offer new avenues for manipulating soft matter phases.
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