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High-pressure cell for simultaneous dielectric and neutron spectroscopy
Alejandro Sanz1, Henriette Wase Hansen1, Bo Jakobsen1
1Glass and Time, IMFUFA, Department of Science and Environment, Roskilde University, P.O. Box 260, DK-4000 Roskilde, Denmark.
The Review of Scientific Instruments
|March 3, 2018
Summary
We developed a novel high-pressure cell for simultaneous dielectric and neutron spectroscopy, enabling simultaneous study of molecular dynamics across multiple time scales. This innovation allows detailed analysis of relaxation and vibrations under extreme conditions.
Area of Science:
- Materials Science
- Spectroscopy
- Physical Chemistry
Background:
- Studying molecular dynamics requires techniques sensitive to various timescales.
- Simultaneous measurements of dielectric and neutron spectroscopy offer complementary insights.
- High pressure is crucial for probing phase transitions and dynamics in condensed matter.
Purpose of the Study:
- To design, manufacture, and test a novel high-pressure cell for simultaneous dielectric and neutron spectroscopy.
- To enable the study of molecular dynamics across picosecond to kilosecond timescales.
- To investigate relaxation and vibrational dynamics under high pressure and varying temperatures.
Main Methods:
- A cylindrical high-pressure cell constructed from a high-strength aluminum alloy.
- Integration of a cylindrical capacitor within the cell for simultaneous capacitance measurements.
- Utilizing backscattering and time-of-flight neutron scattering instruments.
- Conducting experiments on dipropylene glycol across a temperature range of 2–320 K and pressures up to 500 MPa.
Main Results:
- Successful simultaneous collection of dielectric and neutron spectroscopy data.
- Demonstrated capability to probe dynamics from picoseconds to kiloseconds.
- Verified performance across supercooled liquid and glassy states of dipropylene glycol.
- The cell operates reliably up to 500 MPa and temperatures from 2 to 320 K.
Conclusions:
- The developed high-pressure cell is a unique and effective tool for simultaneous dielectric and neutron spectroscopy.
- This setup facilitates comprehensive studies of molecular dynamics under diverse P-T conditions.
- The findings pave the way for deeper understanding of relaxation phenomena and fast dynamics in materials.
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