本研究以發展具放大自發輻射（amplified spontaneous emission， ASE）性質之有機螢光染料為目標，設計並合成一系列以芴（FL）與茚並芴（IndFL）衍生物作為電子供體，並結合苯並雙三唑（BBTA）、苯並雙三唑併咔唑（CTA）、BPNR 與含氮雜芳香單元作為中心受體之對稱共軛分子。透過改變電子供體、受體核心、π 共軛橋接單元與含氮雜環位置，探討分子結構對吸收、螢光放射、螢光量子產率、螢光生命期、輻射速率常數與ASE性質之影響。 第一系列以C₆BBTA為核心，結果顯示(2，2)-C₆BBTA異構物相較於(2，1)-C₆BBTA具有較紅移之吸收與放射波長，說明核心連接位置會影響分子有效共軛與電荷轉移。導入DIndFL供體後，可縮短螢光生命期並提升輻射速率常數，進而降低ASE閾值。第二系列以C₆CTA為核心，導入噻吩（TP）與噻吩并噻吩（TTP）橋接單元後，可延伸π共軛並調控放光波長，其中DIndFL搭配 TTP橋接之分子展現較佳ASE表現。第三系列比較C₆CTA與BPNR核心，結果顯示含較多氮原子之C₆CTA具有較佳受體能力與較低ASE閾值。第四系列以吡啶、噠嗪、嘧啶與吡嗪作為核心，成功發展藍色至藍綠色放光分子，其中吡嗪核心具有較佳螢光效率與ASE性質，而噠嗪核心因螢光效率過低未觀察到明顯 ASE。 此外，本研究建立二次激發ASE量測方法，使待測分子於較接近最大吸收波長條件下被激發。相較於337 nm直接激發，二次激發可大幅降低ASE閾值並減少量測失真。 本研究證明透過調控電子供體、含氮受體核心與π橋接單元，可有效調整有機染料之光物理與ASE性質，並為低閾值、波長可調之有機雷射染料設計提供參考。;This study focuses on the development of organic fluorescent dyes with amplified spontaneous emission (ASE) properties. A series of symmetric conjugated molecules were designed and synthesized using fluorene (FL) and indenofluorene (IndFL) derivatives as electron donors， combined with benzobistriazole (BBTA)， carbazole-fused benzobistriazole (CTA)， BPNR， and nitrogen-containing heteroaromatic units as central acceptor cores. The influence of donor structure， acceptor core， π-bridge， and heteroaromatic isomerism on photophysical and ASE properties was systematically investigated. The C₆BBTA series revealed that core regioisomerism strongly affects absorption and emission wavelengths， while the introduction of DIndFL improved radiative transition efficiency and reduced ASE thresholds. In the C₆CTA series， thiophene and thienothiophene bridges extended π-conjugation and tuned emission wavelengths， with the DIndFL–TTP structure showing better ASE performance. Comparison between C₆CTA and BPNR indicated that the nitrogen-rich C₆CTA core provided stronger acceptor ability and lower ASE thresholds. In the heteroaromatic series， blue to blue-green emissive dyes were obtained， among which the pyrazine-based molecule showed favorable fluorescence and ASE behavior. Furthermore， secondary excitation ASE measurements were established to reduce wavelength-mismatch effects from direct 337 nm excitation， resulting in lower and more reliable ASE thresholds. Overall， this work provides useful design guidelines for low-threshold and wavelength-tunable organic laser dyes.
