Advanced microscopy techniques have provided researchers with an unprecedented glimpse into a molecule. Researchers used the electron beam of a scanning tunnelling microscope (STM) to excite different parts of the molecule, causing it to emit light.

Wilson Ho and his colleagues at the University of California, Irvine, used an STM and photon detector to image molecules of magnesium porphine. The images reveal a structure with twofold symmetry, which the authors say is due to an approximately planar molecule distorting into a saddle shape. This distortion warps molecular orbitals and so changes the spectra of the emitted photons, revealing the inner structure.

Previously, optical techniques have been able to detect individual molecules but not to resolve details of their interiors.

Phys. Rev. Lett. 105, 217402 (2010)