Related Experiment Video
Updated: Oct 5, 2025
10:01
In Situ High Pressure Hydrogen Tribological Testing of Common Polymer Materials Used in the Hydrogen Delivery Infrastructure
Published on: March 31, 2018
7.7K
Structural phase transitions in flexible DUT-8(Ni) under high hydrostatic pressure
Alexander Krylov1, Irina Yushina2, Evgenia Slyusareva3
1Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036, Krasnoyarsk, Russia. shusy@iph.krasn.ru.
Physical Chemistry Chemical Physics : PCCP
|January 27, 2022
Summary
High hydrostatic pressure induces phase transitions in the DUT-8(Ni) metal-organic framework. These transitions, involving gateway vibrations, are influenced by the pressure medium and lead to reversible distorted phases without amorphisation.
Area of Science:
- Materials Science
- Chemistry
- Physics
Background:
- Flexible metal-organic frameworks (MOFs) exhibit dynamic structural responses to external stimuli.
- The DUT-8(Ni) MOF, composed of Ni2(ndc)2(dabco), is known for its porous structure and potential applications.
Purpose of the Study:
- To investigate the pressure-induced phase transitions of DUT-8(Ni) using Raman spectroscopy.
- To elucidate the vibrational modes associated with structural changes under high hydrostatic pressure.
- To understand the influence of pressure-transmitting media on MOF behavior.
Main Methods:
- High-pressure Raman spectroscopy up to 10 GPa.
- Ab initio simulations of vibrational spectra for open pore (op) and closed pore (cp) phases.
- Comparative analysis of experimental and theoretical data.
Main Results:
- The open pore to closed pore (op-cp) transition in DUT-8(Ni) is linked to gateway vibrations (25 and 67 cm-1) involving linker motions.
- New distorted closed pore (cp) phases form above 2 GPa without amorphisation.
- The transition between cp and distorted cp phases is reversible.
- The pressure-transmitting medium significantly affects the phase transition behavior.
Conclusions:
- The study reveals the mechanism of pressure-induced structural transitions in DUT-8(Ni) via gateway vibrations.
- The formation of reversible distorted cp phases highlights the framework's adaptability under pressure.
- The choice of pressure-transmitting medium is critical for controlling phase transitions in flexible MOFs.
More Related Videos
05:04Determining the Mechanical Strength of Ultra-Fine-Grained Metals
Published on: November 22, 2021
2.4K
08:42High-Sensitivity Nuclear Magnetic Resonance at Giga-Pascal Pressures: A New Tool for Probing Electronic and Chemical Properties of Condensed Matter under Extreme Conditions
Published on: October 10, 2014
11.7K
Related Concept Videos
01:19Phase Diagram
6.2K
The phase of a given substance depends on the pressure and temperature. Thus, plots of pressure versus temperature showing the phase in each region provide considerable insights into the thermal properties of substances. Such plots are known as phase diagrams. For instance, in the phase diagram for water (Figure 1), the solid curve boundaries between the phases indicate phase transitions (i.e., temperatures and pressures at which the phases coexist).
6.2K
01:24Stress-Strain Diagram - Ductile Materials
1.0K
The stress-strain relationship in ductile materials such as structural steel or aluminium is intricate and progresses through several stages. When a specimen is loaded, it initially exhibits a linear length increase, depicted by a steep straight line on the stress-strain diagram. It indicates the material is elastically deforming and will return to its original shape once unloaded. However, when a critical stress value is reached, plastic deformation begins. This stage sees substantial...
1.0K
02:39Phase Diagrams
44.8K
A phase diagram combines plots of pressure versus temperature for the liquid-gas, solid-liquid, and solid-gas phase-transition equilibria of a substance. These diagrams indicate the physical states that exist under specific conditions of pressure and temperature and also provide the pressure dependence of the phase-transition temperatures (melting points, sublimation points, boiling points). Regions or areas labeled solid, liquid, and gas represent single phases, while lines or curves represent...
44.8K
02:31Phase Transitions
20.6K
Whether solid, liquid, or gas, a substance's state depends on the order and arrangement of its particles (atoms, molecules, or ions). Particles in the solid pack closely together, generally in a pattern. The particles vibrate about their fixed positions but do not move or squeeze past their neighbors. In liquids, although the particles are closely spaced, they are randomly arranged. The position of the particles are not fixed—that is, they are free to move past their neighbors to...
20.6K
01:18Residual Stresses in Bending
297
In the study of elastoplastic members subjected to bending moments, understanding the loading and unloading phases is crucial for assessing material behavior and structural integrity. During the loading phase, as the bending moment increases, the material initially responds elastically, adhering to Hooke's Law, where stress is directly proportional to strain. When the load exceeds the yield strength, plastic deformation occurs, resulting in permanent strain and deformation that remains even...
297
01:04Hydrostatic Pressure Force on a Curved Surface
2.1K
Hydrostatic pressure on curved surfaces is a fundamental concept in fluid mechanics with broad applications in the civil engineering field. When fluid is in contact with a curved surface, as in a reservoir, dam, or storage tank, it exerts pressure that varies in magnitude and direction along the curved surface. To assess the total hydrostatic force exerted by the fluid on a curved structure, engineers typically isolate the fluid volume adjacent to the surface and analyze the forces acting on...
2.1K