Synthesis and two-photon absorption property of a series of metal–salen compounds containing a variety of thiophene moieties

A series of metal–salen coordination compounds (where M is Cu2 + or Ni2 +, and the salen ligands contain various thiophene moieties) have been designed, synthesized and characterized. Both one-photon and two-photon absorption (2PA) properties have been investigated. Non-degenerate 2PA (ND-2PA) and open-aperture Z-scan measurements indicate that several of the complexes exhibit 2PA in the wavelength range of 600–700 nm with sizable 2PA cross-sections (σ2PA) of 900–2200 GM.