About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Thermodynamics and Kinetics
|
Presentation Title |
Does Vibrational Motion Explain the Latent Heat of Melting in Materials? |
Author(s) |
Camille M. Bernal-Choban, Claire N Saunders, Stefan Lohaus, Doug Abernathy, Brent Fultz |
On-Site Speaker (Planned) |
Camille M. Bernal-Choban |
Abstract Scope |
It is well established that atomic vibrations dominate the entropy of solids and liquids. The challenge persists in determining if the difference in vibrational entropy upon melting is larger than the change in entropy from other sources. Inelastic neutron scattering (INS) measurements were performed on powder samples of Ge, Sn, Pb, and Bi from room temperature to 200 K above the melting temperature of each material. Experimental vibrational spectra were processed using customized multiphonon and multiple scattering corrections. Subsequent analysis, informed by vibrational-transit theory, was used to calculate the vibrational density of states (DOS) for each phase. Preliminary results for Ge showed that the difference between the solid and liquid DOS accounts for over 50% of the latent heat. The separation of diffusional versus collective motion through melting will also be discussed. Similar methods and analysis will be presented for Sn, Pb, and Bi. |
Proceedings Inclusion? |
Planned: |
Keywords |
Computational Materials Science & Engineering, Phase Transformations, Other |