# Discrete Dipole Approximation for Low-Energy Photoelectron Emission from NaCl Nanoparticles

## Abstract

This work presents a model for the photoemission of electrons from sodium chloride nanoparticles 50-500 nm in size, illuminated by vacuum ultraviolet light with energy ranging from 9.4-10.9 eV. The discrete dipole approximation is used to calculate the electromagnetic field inside the particles, from which the two-dimensional angular distribution of emitted electrons is simulated. The emission is found to favor the particle?s geometrically illuminated side, and this asymmetry is compared to previous measurements performed at the Lawrence Berkeley National Laboratory. By modeling the nanoparticles as spheres, the Berkeley group is able to semi-quantitatively account for the observed asymmetry. Here however, the particles are modeled as cubes, which is closer to their actual shape, and the interaction of an emitted electron with the particle surface is also considered. The end result shows that the emission asymmetry for these low-energy electrons is more sensitive to the particle-surface interaction than to the specific particle shape, i.e., a sphere or cube.

- Authors:

- Publication Date:

- Research Org.:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

- Sponsoring Org.:
- Chemical Sciences Division

- OSTI Identifier:
- 1052183

- Report Number(s):
- LBNL-5236E

- DOE Contract Number:
- DE-AC02-05CH11231

- Resource Type:
- Journal Article

- Journal Name:
- Journal of Quantitative Spectroscopy&Radiative Transfer

- Additional Journal Information:
- Journal Name: Journal of Quantitative Spectroscopy&Radiative Transfer

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 99; 37; Discrete, Dipole, Approximation, Low-Energy Photoelectron, Emission

### Citation Formats

```
Berg, Matthew J., Wilson, Kevin R., Sorensen, Chris, Chakrabarti, Amit, and Ahmed, Musahid.
```*Discrete Dipole Approximation for Low-Energy Photoelectron Emission from NaCl Nanoparticles*. United States: N. p., 2011.
Web.

```
Berg, Matthew J., Wilson, Kevin R., Sorensen, Chris, Chakrabarti, Amit, & Ahmed, Musahid.
```*Discrete Dipole Approximation for Low-Energy Photoelectron Emission from NaCl Nanoparticles*. United States.

```
Berg, Matthew J., Wilson, Kevin R., Sorensen, Chris, Chakrabarti, Amit, and Ahmed, Musahid. Thu .
"Discrete Dipole Approximation for Low-Energy Photoelectron Emission from NaCl Nanoparticles". United States. https://www.osti.gov/servlets/purl/1052183.
```

```
@article{osti_1052183,
```

title = {Discrete Dipole Approximation for Low-Energy Photoelectron Emission from NaCl Nanoparticles},

author = {Berg, Matthew J. and Wilson, Kevin R. and Sorensen, Chris and Chakrabarti, Amit and Ahmed, Musahid},

abstractNote = {This work presents a model for the photoemission of electrons from sodium chloride nanoparticles 50-500 nm in size, illuminated by vacuum ultraviolet light with energy ranging from 9.4-10.9 eV. The discrete dipole approximation is used to calculate the electromagnetic field inside the particles, from which the two-dimensional angular distribution of emitted electrons is simulated. The emission is found to favor the particle?s geometrically illuminated side, and this asymmetry is compared to previous measurements performed at the Lawrence Berkeley National Laboratory. By modeling the nanoparticles as spheres, the Berkeley group is able to semi-quantitatively account for the observed asymmetry. Here however, the particles are modeled as cubes, which is closer to their actual shape, and the interaction of an emitted electron with the particle surface is also considered. The end result shows that the emission asymmetry for these low-energy electrons is more sensitive to the particle-surface interaction than to the specific particle shape, i.e., a sphere or cube.},

doi = {},

journal = {Journal of Quantitative Spectroscopy&Radiative Transfer},

number = ,

volume = ,

place = {United States},

year = {2011},

month = {9}

}