There was a period when “visualize a quantum orbital” meant downloading a 600 KB Windows program from somebody’s personal website.
David Manthey’s Orbital Viewer first appeared in 1998 and was still being updated in 2004. The download page supports a wonderfully specific range of systems: Windows 95, 98, NT 4.0, 2000, ME, XP, and even Windows 3.1x with Win32s.
The program does much more than draw the familiar dumbbell-shaped p orbital.
Chemistry rendered like graphics software
Orbital Viewer can draw atomic orbitals with principal quantum number up to 30 and build molecular orbitals using linear combinations of atomic orbitals.
Rendering options include probability-point plots, polygon surfaces, and ray tracing. The program can show asymptotes, cut away parts of an orbital to reveal internal structure, apply translucence and refraction, add lighting and shadows, and produce animations.
It also supports several forms of stereo viewing: red-blue anaglyphs, stereograms, stereoscopes, LCD shutter glasses, Chromadepth, and overlays.
Output formats include TIFF, PPM, BMP, AVI, and VRML.
That feature list is a small time capsule of late-1990s scientific visualization. VRML mattered. AVI export mattered. A 1.8 MB PDF manual counted as a substantial companion download.
The site’s news archive preserves the software’s development history: version 1.00 in March 1998, later bug fixes, added Digistar output, hosting changes, and a 2004 release that made stereo colors configurable.
The page is valuable because it preserves both the program and the assumptions around it. Scientific visualization did not always happen in a browser or notebook environment. It could be a tiny downloadable executable maintained by one person for years.
CacheRat’s 1,967 Ancient Web Domains research list contains many examples of useful software surviving because its author kept the old download page online.
Orbital Viewer is one of the better ones: serious math, serious rendering, and a file small enough to fit on a floppy disk.