Electronic Absorption, Emission and Two-PhotonAbsorption Properties of Some Functional1,3,5-Triphenylbenzenes

Abstract

We report herein the linear optical properties of some extended 1,3,5‐triphenylbenzene derivatives 1,3,5‐[(1, 4‐C6H4)C≡C(4‐C6H4X)]3(C6H3) (3‐X; X=NO2, CN, H, OMe, NMe2, NPh2) and briefly discuss the two‐photon absorption (2PA) cross‐sections determined for the derivatives featuring the most electron‐rich substituents, contrasting their 2PA performance with the 2PA values previously gathered for their triphenylisocyanurate analogues N,N’,N”‐[(1, 4‐C6H4)C≡C(4‐C6H4X)]3(N3{C(O)}3) (1‐X). When functionalized by electron‐releasing substituents at their periphery, 3‐X derivatives are potent substitutes for 1‐X compounds in NLO applications, especially when maximal transparency is not required in the visible range. Some rationalization of this unexpected outcome is proposed based on DFT calculations.