Two-photon materials with large two-photon cross sections. Structure-property relationship.

The development of two-photon materials has been growing very fast during the last decade due to the potential applications in optical limiting, 3D microfabrication, and multiphoton microscopy. In this article, the structure-two-photon absorption property relationships of dipolar, quadrupolar, and octupolar molecules as well as the derivatives of triphenylamine, [2.2]paracyclophanes, multi-annulenes, and porphyrins are briefly reviewed to provide a guideline for the design of efficient two-photon materials.