#### Event Title

Structural Analysis of a 2-D Micron-Scale Particle Array

#### Graduation Year

2013

#### Location

Atrium, Center for Natural Sciences, Illinois Wesleyan University

#### Start Date

20-4-2013 2:00 PM

#### End Date

20-4-2013 3:00 PM

#### Description

General diffraction theory is commonly applied in analyzing crystal structures through x-ray diffraction. However, by using polystyrene spheres with diameters in the micron range, we can observe diffraction directly with visible light. By putting a monolayer of spheres in solution on a glass slide and passing a laser though onto a screen, we observe the distinct diffraction pattern as surface tension draws the spheres into a two-dimensional array. Then, with the help of image processing software, we can take intensity measurements of different regions of the diffraction pattern, calculate lattice spacing of the spheres' lattice in real space, calculate the radial distribution function, and measure the diameter of the spheres to compare with their expected value.

Structural Analysis of a 2-D Micron-Scale Particle Array

Atrium, Center for Natural Sciences, Illinois Wesleyan University

General diffraction theory is commonly applied in analyzing crystal structures through x-ray diffraction. However, by using polystyrene spheres with diameters in the micron range, we can observe diffraction directly with visible light. By putting a monolayer of spheres in solution on a glass slide and passing a laser though onto a screen, we observe the distinct diffraction pattern as surface tension draws the spheres into a two-dimensional array. Then, with the help of image processing software, we can take intensity measurements of different regions of the diffraction pattern, calculate lattice spacing of the spheres' lattice in real space, calculate the radial distribution function, and measure the diameter of the spheres to compare with their expected value.