Electron orbitals of excited hydrogen atoms can be observed directly.

Orbitals lie outside the nucleus and their properties are described by mathematical wavefunctions. These functions are difficult to study because measuring observable components can destroy other quantum features. Aneta Stodolna at the FOM Institute for Atomic and Molecular Physics in Amsterdam, Marc Vrakking at the Max Born Institute in Berlin and their colleagues designed a quantum microscope to study hydrogen orbitals directly. Their system used tunable lasers to excite electrons in a hydrogen atom placed in an electric field. An electrostatic lens then stretched and magnified the orbitals — without disturbing the internal structure — until individual electrons hit a detector. After recording about 50,000 electrons, the team produced images to show the structure of the electron orbital (pictured) of atoms at different excited states.

Credit: ANETA STODOLNA/MARC VRAKKING

Phys. Rev. Lett. 110, 213001 (2013)