Beautiful 'flowers' self-assemble in a beaker

By simply manipulating chemical gradients in a beaker of fluid, materials scientists at Harvard have found that they can control the growth behavior of crystals to create precisely tailored structures—such as delicate, micron-scale flowers.

"Spring is like a perhaps hand," wrote the poet E. E. Cummings: "carefully / moving a perhaps / fraction of flower here placing / an inch of air there... / without breaking anything."

With the hand of nature trained on a beaker of chemical fluid, the most delicate flower structures have been formed in a Harvard laboratory—and not at the scale of inches, but microns.

These minuscule sculptures, curved and delicate, don't resemble the cubic or jagged forms normally associated with crystals, though that's what they are. Rather, fields of carnations and marigolds seem to bloom from the surface of a submerged glass slide, assembling themselves a molecule at a time.