Related Experiment Video
Updated: Jun 14, 2026
06:50
An Experimental Protocol for Studying Mineral Effects on Organic Hydrothermal Transformations
Published on: August 8, 2018
Communications: High-temperature water under pressure
Takashi Ikeda1, Yoshinori Katayama, Hiroyuki Saitoh
1Synchrotron Radiation Research Unit, Quantum Beam Science Directorate, Japan Atomic Energy Agency (JAEA), 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan. ikeda.takashi@jaea.go.jp
The Journal of Chemical Physics
|April 8, 2010
Summary
Investigating liquid water under varying temperature and pressure reveals a transition from an H-bonded to a simple-liquid state. This change in water
Area of Science:
- Physical Chemistry
- Materials Science
- Condensed Matter Physics
Background:
- Understanding the behavior of liquid water under extreme conditions is crucial for various scientific disciplines.
- Water exhibits complex structural, dynamical, and electronic properties influenced by temperature and pressure.
Purpose of the Study:
- To systematically investigate the effects of temperature and pressure on liquid water's properties.
- To identify phase transitions or crossovers in the liquid water phase diagram.
Main Methods:
- Utilizing first-principles molecular dynamics simulations.
- Employing in situ x-ray diffraction for experimental validation.
Main Results:
- Observed significant changes in structural, dynamical, and electronic properties of liquid H(2)O.
- Identified a crossover from a hydrogen-bonded liquid to a simple-liquidlike state with increasing temperature.
Conclusions:
- The study provides insights into the complex phase behavior of water.
- A transition in liquid water's nature is confirmed under specific thermodynamic conditions.
Related Concept Videos
01:19Phase Diagram
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).
01:24Phase Diagram
A phase diagram is a graphical representation of the physical states of a substance under different conditions of temperature and pressure. It shows the boundaries between solid, liquid, and gas phases and the conditions at which these phases coexist in equilibrium. An area in a phase diagram represents a single phase, whereas lines or phase boundaries represent the equilibrium between two phases.In the phase diagram of water, the boundary line between the solid and liquid states illustrates...
01:11Temperature and Thermal Equilibrium
Heat and temperature are essential concepts for everyone every day. The study of heat and temperature is part of an area of physics known as thermodynamics. It is not always easy to distinguish heat and temperature.
The concept of temperature has evolved from the common concepts of hot and cold. The scientific definition of temperature explains more than just our sense of hot and cold. Temperature is operationally defined as the quantity measured with a thermometer. Furthermore, temperature is...
The concept of temperature has evolved from the common concepts of hot and cold. The scientific definition of temperature explains more than just our sense of hot and cold. Temperature is operationally defined as the quantity measured with a thermometer. Furthermore, temperature is...
01:28Vapor Pressure of Fluid
The vapor pressure of a fluid is a crucial concept in fluid mechanics, influencing phenomena such as boiling and cavitation. Vapor pressure refers to the pressure exerted by a vapor at a state of thermodynamic equilibrium with its corresponding liquid phase at a specific temperature. It represents the tendency of molecules to escape from the fluid surface into the vapor phase.
When a liquid is placed in a closed container with a small air space, and the space is evacuated, vapor molecules will...
When a liquid is placed in a closed container with a small air space, and the space is evacuated, vapor molecules will...
01:21Isothermal Processes
A thermodynamic process that occurs at constant temperature is called an isothermal process. Heat slowly flows into the system or out of the system to maintain thermal equilibrium. Processes involving phase changes like water evaporation into steam or freezing water into ice at a constant temperature are examples of Isothermal Processes.
An ideal gas can also undergo isothermal expansion or compression.
For example, consider 1 mole of an ideal gas inside an isolated cylinder at initial volume V...
An ideal gas can also undergo isothermal expansion or compression.
For example, consider 1 mole of an ideal gas inside an isolated cylinder at initial volume V...
01:21Multiple Pipe Systems
Multipipe systems consist of complex configurations of interconnected pipes designed to transport fluids efficiently across intricate networks. They are essential in engineering applications requiring precise control over flow distribution, pressure, and head loss. They are categorized into series, parallel, loop, and network configurations, each distinguished by unique flow characteristics and applications.
Series Configuration
In a series configuration, fluid flows sequentially from one pipe...
Series Configuration
In a series configuration, fluid flows sequentially from one pipe...