以萘为π-中心的双芪类衍生物双光子上转换荧光性能研究

研究了2个新的双光子上转换荧光分子—1,4-双-(9-乙基咔唑基)萘(简称为BECVN)和1,4-双-(4’-N,N-二甲氨基苯乙烯基)萘(简称为BMABN)的单光子、双光子光谱性质。在～375 nm Xe灯光源激发下，两样品的DMF溶液发出很强的蓝、绿色荧光(峰位492～541 nm)，视感效果非常明显。BMABN分子的线性吸收/发射光谱的峰位与BECVN分子相比，均发生红移;相对荧光量子产率(Φ_f)比BECVN降低了7.4倍。在飞秒钛宝石激光器泵浦下(760 nm)，两样品的DMF溶液发出强的双光子上转换荧光发射，峰位与单光子荧光峰位相比发生红移(500～556 nm)。BMABN的双光子荧光强度和双光子吸收截面分别是BECVN的3倍和30.4倍。

Study on Two-Photon Induced Fluorescence of Newly Synthesized Chromophore BECVN and BMABN

One-photon fluorescence(OPF) and two-photon fluorescence (TPF) of two chromophores 1,4-bis(9-ethyl-vinyl carbazole) naphthalene (abbreviated as BECVN) and 1,4-bis(4-N, N-methylamino styryl) naphthalene (abbreviated as BMABN) were resported. Strong emission at 492-541 nm and at 500-556 nm, respectively, were obtained under the excitation of -370 nm (Xe lamp) and of 730-800 nm femto-second laser pulses, respectively. Although the relative fluorescence quantum yield (phi(f)) of BECVN is as high as 7.4 times that of BMABN, the latter possesses higher TPF intensity and larger two-photon absorption (TPA) cross-section, suggesting that BMABN containing naphthalene as pi-center end-capped with N,N-methylamino styryl group exhibits more effective two-photon process. Lippert equation showed that the difference of dipole momnet (deltamu(ge)) between the ground state and the excited state for BECVN is nearly twice that for BMABN, conforming to that the deltamu(ge) value is not the key for the enhancement of two-photon absorption cross-section.