### Multiphonon: Phonon Density of States tools for Inelastic Neutron Scattering Powder Data

The multiphonon python package calculates phonon density of states, a reduced representation of vibrational property of condensed matter (see, for example, Section “Density of Normal Modes” in Chapter 23 “Quantum Theory of the Harmonic Crystal” of (Ashcroft and Mermin 2011)), from inelastic neutron scattering (see, for example (B. Fultz et al. 2006–2016)) spectrum from a powder sample. Inelastic neutron spectroscopy (INS) is a probe of excitations in solids of vibrational or magnetic origins. In INS, neutrons can lose(gain) energy to(from) the solid in the form of quantized lattice vibrations – phonons. Measuring phonon density of states is usually the first step in determining the phonon properties of a material experimentally. Phonons play a very important role in understanding the physical properties of a solid, including thermal conductivity and electrical conductivity. Hence, INS is an important tool for studying thermoelectric materials (Budai et al. 2014, Li et al. (2015)), where low thermal conductivity and high electrical conductivity are desired. Study of phonon entropy also made important contributions to the research of thermal dynamics and phase stability of materials (B. Fultz 2010, bogdanoff2002phonon, swan2006vibrational).

- Publication Date:

- Grant/Contract Number:
- AC05-00OR22725

- Type:
- Accepted Manuscript

- Journal Name:
- Journal of Open Source Software

- Additional Journal Information:
- Journal Volume: 3; Journal Issue: 21; Journal ID: ISSN 2475-9066

- Publisher:
- Open Source Initiative - NumFOCUS

- Research Org:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

- Sponsoring Org:
- USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 36 MATERIALS SCIENCE; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

- OSTI Identifier:
- 1422991

```
Y. Y. Lin, Jiao, Islam, Fahima, and Kresh, Max.
```*Multiphonon: Phonon Density of States tools for Inelastic Neutron Scattering Powder Data*. United States: N. p.,
Web. doi:10.21105/joss.00440.

```
Y. Y. Lin, Jiao, Islam, Fahima, & Kresh, Max.
```*Multiphonon: Phonon Density of States tools for Inelastic Neutron Scattering Powder Data*. United States. doi:10.21105/joss.00440.

```
Y. Y. Lin, Jiao, Islam, Fahima, and Kresh, Max. 2018.
"Multiphonon: Phonon Density of States tools for Inelastic Neutron Scattering Powder Data". United States.
doi:10.21105/joss.00440. https://www.osti.gov/servlets/purl/1422991.
```

```
@article{osti_1422991,
```

title = {Multiphonon: Phonon Density of States tools for Inelastic Neutron Scattering Powder Data},

author = {Y. Y. Lin, Jiao and Islam, Fahima and Kresh, Max},

abstractNote = {The multiphonon python package calculates phonon density of states, a reduced representation of vibrational property of condensed matter (see, for example, Section “Density of Normal Modes” in Chapter 23 “Quantum Theory of the Harmonic Crystal” of (Ashcroft and Mermin 2011)), from inelastic neutron scattering (see, for example (B. Fultz et al. 2006–2016)) spectrum from a powder sample. Inelastic neutron spectroscopy (INS) is a probe of excitations in solids of vibrational or magnetic origins. In INS, neutrons can lose(gain) energy to(from) the solid in the form of quantized lattice vibrations – phonons. Measuring phonon density of states is usually the first step in determining the phonon properties of a material experimentally. Phonons play a very important role in understanding the physical properties of a solid, including thermal conductivity and electrical conductivity. Hence, INS is an important tool for studying thermoelectric materials (Budai et al. 2014, Li et al. (2015)), where low thermal conductivity and high electrical conductivity are desired. Study of phonon entropy also made important contributions to the research of thermal dynamics and phase stability of materials (B. Fultz 2010, bogdanoff2002phonon, swan2006vibrational).},

doi = {10.21105/joss.00440},

journal = {Journal of Open Source Software},

number = 21,

volume = 3,

place = {United States},

year = {2018},

month = {1}

}