Wave-particle duality is a model used to describe how all matter has both wave and particle properties. For example, under certain conditions, electrons can be made to diffract. They spread out like waves as they pass through a tiny gap (thin slice of polycrystalline graphite – has spacing between carbon atoms). This forms an interference pattern on a screen (2 concentric rings).
- Electrons act as waves; they diffract.
- The gaps between atoms are similar to the wavelength of the electrons.
- The polycrystalline graphite forms a regular pattern, like diffraction grating.
- Interference occurs of diffracted electrons.
- All possible crystal orientations gives two concentric rings.
The de Broglie equation treats all of matter as waves. It yields the equation:
As particles become larger, their wave like properties become more difficult to observe. This is because a larger mass leads to a larger momentum and therefore a smaller wavelength.