It's more efficient than traditional methods, but still computationally demanding due to the large number of potential compounds to test. The team analyzed the Hf-Ta-C material for which the melting point had already been experimentally determined. The simulation was able to elucidate some of the factors that contribute to the material's remarkable heat tolerance.
The work shows that Hf-Ta-C combined a high heat of fusion the energy released or absorbed when it transitions from solid to liquid with a small difference between the entropies disorder of the solid and liquid phases. Researchers then used those findings to look for compounds that might maximize those properties. They found that a compound with hafnium, nitrogen, and carbon would have a similarly high heat of fusion but a smaller difference between the entropies of the solid and the liquid.
When they calculated the melting point using their computational approach, it came out K higher than the experimental record. The group is now collaborating with Alexandra Navrotsky's lab at the University of California, Davis, to synthesize the compound and perform the melting point experiments.
Navrotksy's lab is equipped for such high-temperature experiments. The higher the temperature, the faster the molecules move, or the faster they vibrate. In a solid, as the molecules vibrate more strongly, at some temperature they will have enough speed and energy to break from the rigid structure and move around past each other. This is when they become a liquid. So the melting point is the temperature at which molecules in a solid can move past each other and form a liquid.
The boiling point, on the other hand, involves liquids and gases. As liquid molecules are moving around, some molecules at the surface of the liquid are escaping. Skip to main content. States of Matter. Search for:. Melting Point Learning Objectives Define melting point. Describe the process of particle movement in melting. Describe the forces that influence the melting point of a material.
Examples Have you ever gone ice skating? Key Takeaways Summary The melting point is the temperature at which a solid changes into a liquid. Intermolecular forces have a strong influence on melting point. How can we use melting point data to help identify a compound?
How can we use melting points to assess the purity of a compound? Exercises Review Questions Define melting point. What happens when a material melts?
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