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We introduce a lattice dynamics package which calculates elastic, thermodynamic and thermal transport properties of crystalline materials from data on their force and potential energy as a function of atomic positions. The data can come from density functional theory (DFT) calculations or classical molecular dynamics runs performed in a supercell. First, the model potential parameters, which are anharmonic force constants are extracted from the latter runs. Then, once the anharmonic model is defined, thermal conductivity and equilibrium properties at finite temperatures can be computed using lattice dynamics, Boltzmann transport theories, and a variational principle respectively. In addition, the software calculates the mechanical properties such as elastic tensor, Gruneisen parameters and the thermal expansion coefficient within the quasi-harmonic approximation (QHA). Phonons, elastic constants and thermodynamic properties results applied to the germanium crystal will be illustrated. Using the force constants as a force field, one may also perform molecular dynamics (MD) simulations in order to investigate the combined effects of anharmonicity and defect scattering beyond perturbation theory.
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Elastic scattering measurements of 7Be+natZr at sub- and near – barrier energies
We will present a recent experiment for elastic scattering of 7Be+natZr at five sub – and near- barrier energies, namely at 21.5, 22.5, 24, 27 and 28 MeV, for determining the optical potential. The experiment was performed at the TriSol radioactive beam facility of Notre Dame University, simultaneously with elastic scattering and breakup measurements of 8B+90Zr , the last performed at 28MeV. This optical potential will be used as one of the coupling potentials in our CDCC calculations for 8B. Further more we will look for the energy dependence of the potential and its resemblance to either the one exhibited by 7Li or the one by 6Li, extracting useful conclusions about their structure. Preliminary data are presented and discussed.
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- Award ID(s):
- 2011890
- PAR ID:
- 10519979
- Publisher / Repository:
- ePublishing
- Date Published:
- Journal Name:
- HNPS Advances in Nuclear Physics
- Volume:
- 29
- ISSN:
- 2654-007X
- Page Range / eLocation ID:
- 52 to 57
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.12681/hnpsanp.5006
