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Updated: Apr 18, 2026
08:27
Aqueous Droplets Used as Enzymatic Microreactors and Their Electromagnetic Actuation
Published on: August 28, 2017
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Nanometer-sized dynamic entities in an aqueous system.
E Mamontov1, P Zolnierczuk, M Ohl
1Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6473, USA. mamontove@ornl.gov.
Physical Chemistry Chemical Physics : PCCP
|January 13, 2015
Summary
Water molecules exhibit unique slow dynamics in aqueous solutions, distinct from localized movements. This discovery offers new insights into the complex dynamics of glass-forming liquids.
Area of Science:
- Condensed matter physics
- Physical chemistry
- Materials science
Background:
- Water exhibits complex dynamics, including localized motions and structural relaxations.
- Understanding these dynamics is crucial for various applications, especially in glass-forming liquids.
- Existing techniques struggle to probe slower dynamics on specific length scales.
Purpose of the Study:
- To investigate the center-of-mass dynamics of water molecules in aqueous solutions at low temperatures.
- To characterize the time and length scales of these dynamics.
- To explore the connection between these dynamics and slow secondary relaxations in glass-forming liquids.
Main Methods:
- Neutron spin-echo (NSE) spectroscopy
- Backscattering spectroscopy
- Probing dynamics on nanosecond time and nanometer length scales
Main Results:
- Observed distinct center-of-mass dynamics of water molecules, differing from localized and structural relaxations.
- Characterized these slower motions occurring on nanosecond time and nanometer length scales.
- Associated these dynamics with slow secondary relaxations (excess wing dynamics) in glass-forming liquids.
Conclusions:
- Neutron spectroscopy can probe slow dynamics in glass-forming liquids.
- Identified a new type of water molecule dynamics relevant to secondary relaxations.
- Provides a method to study characteristic length scales of dynamic entities in glass-forming liquids.
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