Abstract
Inelastic neutron scattering and nuclear resonant inelastic x-ray scattering were used to determine the phonon densities of states of face-centered-cubic Ni-Fe alloys. Increasing Fe concentration results in an average softening of the phonon modes. Chemical ordering of the Ni 0.72 Fe 0.28 alloy results in a reduction of the partial vibrational entropy of the Fe atoms but does not significantly change the partial vibrational entropy of the Ni atoms. Changes in the phonon densities of states with composition and chemical ordering are discussed and analyzed with a cluster expansion method.
| Original language | English |
|---|---|
| Article number | 17A308 |
| Journal | Journal of Applied Physics |
| Volume | 113 |
| Issue number | 17 |
| DOIs | |
| State | Published - May 7 2013 |
Funding
A portion of this research at ORNL's Spallation Neutron Source was sponsored by the Scientific User Facilities Division, Office of Basic Energy Sciences, U.S. Department of Energy. This work was supported by the Department of Energy through the Basic Energy Sciences Grant No. DE-FG02-03ER46055 and BES-MS, W-31-109-ENG-38. Portions of this work were performed at HPCAT (Sector 16), Advanced Photon Source (APS), Argonne National Laboratory. Use of the HPCAT facility was supported by DOE-BES, DOE-NNSA (CDAC), NSF, DOD TACOM, and the W.M. Keck Foundation. Use of the APS was supported by DOE-BES, under Contract No. DE-AC02-06CH11357. This work benefitted from danse software developed under NSF Grant No. DMR-0520547.
| Funders | Funder number |
|---|---|
| BES-MS | W-31-109-ENG-38 |
| CDAC | |
| DOE-BES | |
| DOE-NNSA | |
| Scientific User Facilities Division | |
| National Science Foundation | |
| U.S. Department of Defense | |
| U.S. Department of Energy | |
| W. M. Keck Foundation | DE-AC02-06CH11357, DMR-0520547 |
| Basic Energy Sciences | DE-FG02-03ER46055 |