Synthesis,Crystal Structure and Two-photon Absorption Properties of 4′-(N,N-di(4-hydroxymethyl phenyl) amino)phenyl-2,2′:6′,2'-terpyridine

A novel donor-acceptor(D-A) triphenylamino terpyridine derivative L was facilely synthesized and fully characterized, and its single crystals were obtained and determined by X-ray diffraction analysis. It crystallizes in triclinic, space group P1 with a = 11.760(5), b =12.516(5), c = 12.850(5) , α = 67.141(5), β = 65.284(5), γ = 75.876(5)o, Mr = 621.54, V = 1575.6(11) 3, Z = 2, Dc = 1.310 g/cm3, μ = 0.245 mm-1, F(000) = 648, the final R = 0.0671 and w R = 0.1869 for 11328 observed reflections with Ⅰ 2σ(Ⅰ). Linear and nonlinear optical properties of terpyridine derivative L were systematically investigated. The maximum two-photon cross-section of L was 382.5 GM(Goeppert-Mayer), measured by two-photon excited fluorescence(TPEF) method. This result demonstrates that the increase of intramolecular charge transfer(ICT) leads to enhanced two-photon absorption(2PA), which could be achieved by introducing additional electron-donor groups to the molecular framework.