Math Trek Math

Crystal Möbius

By Ivars Peterson

- More than 2 years ago

Take a ribbon of paper, twist one end 180 degrees, and attach it to the other end. The resulting surface, called a Möbius strip, has only one side and one edge.

Scanning electron microscope image shows niobium selenide crystals in a Möbius-strip conformation (top). In the schematic diagram (bottom), a white ribbon represents a niobium selenide crystal with a 180-degree twist and a red sphere represents a selenium droplet.