Visualizing electronic density of atoms and molecules with AViz

Joey Fox, Or Cohen, Eduardo Warszawski   and Joan Adler

The three-dimensional  nature of the electronic wavefunctions
of the hydrogen atom  for different states is subtle and almost impossible
to comprehend from a two dimensional drawing. Using an ``off label''
implementation of the the AViz atomistic visualization package we have
created three dimensional visualizations showing clearly the geometry
of different states.

Dots with densities corresponding to the electronic probability density
and color coding to emphasise more dense regions as well as slicing and 
rotation to aid depth perception.
For the hydrogen atom, the densities can be calculated from the
analytic solution. For other cases numerical solution of the Schroedinger 
equation is needed, nevertheless,
this approach has been extended to more complex systems.
Density Functional Theory was applied  to  lithium atoms 
as well as to hydrogen, methane and ethylene  molecules. 
Further directions such as observing the difference between
sp2 and sp3 states in carbon are also being explored on the way to
visualizing the electron densities of carbon atoms in a lattice.

This approach has applications to both Physics Education 
(modern physics and quantum mechanics courses)
and to research.


Links to the visualizations can be found at
http://phycomp.technion.ac.il/~phr76ja/IPSabstract.html
We thank Leeor Kronik for advice on  Density Functional theory and software.
[Abstract in pdf] [AViz website] [ Joey's site][ Or's site] [ Eduardo's color instructions][final poster pdf]