This 3D rendering depicts a 2p electron orbital. The 2p orbital's wavefunction is orange where positive, and blue where negative. The density of the volume is directly proportional to the electron's probability density. This participating media is rendered with transmission, absorption, and scattering (two indirect bounces) interactions. The goal of this is to more clearly demonstrate what the wavefunctions of atomic orbitals look like, since most common depictions only render a solid shell inside which electrons are likely to be found at least some percentage of the time.
<a href="//commons.wikimedia.org/w/index.php?title=User:Miles_Waugh&amp;action=edit&amp;redlink=1" class="new" title="User:Miles Waugh (page does not exist)">Miles Waugh</a>
CC BY 4.0
<span class="int-own-work" lang="en">Own work</span>