BP Molecules, George Triantafyllakos's free molecular display font from 2008, builds its letters from dots and connecting rods that read like a playful chemistry diagram. The caps feel airy and skeletal, with round nodes doing most of the visual work while the thin links keep the forms light and a little nerdy.
That makes this free font a natural pick for science fair graphics, lab posters, STEM event branding, classroom worksheets, and techy title cards where the molecular motif can carry the idea fast. It also works for short headlines and monograms, because the letters behave like tiny structures rather than plain lettering.