Department of Dyestuff Technology, Institute of Chemical Technology, (Formerly UDCT), Nathalal Parekh Marg, Matunga, Mumbai 400019, India.
Centre for Molecular and Biophysics Research, Department of Physics, Mar Ivanios College, Thiruvananthapuram, Kerala 695015, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2019 May 15;215:122-129. doi: 10.1016/j.saa.2019.02.097. Epub 2019 Feb 24.
BOPHY (BPY) and BODIPY (BDY) dye bearing benzyl group (Bn) at 4,4' and 2,6 position respectively were synthesized and characterized. The fluorescence decay measurements were performed which reveal that benzyl BOPHY (Bn-BPY) has shorter fluorescence lifetime compared to benzyl BODIPY (Bn-BDY). The difference in transition dipole moment is found to be 6.93 and 11.3 D for Bn-BDY and Bn-BPY respectively in toluene. The molecular electrostatic potential (MEP) plot shows Bn-BDY is more polarised compared to Bn-BPY. The nonlinear optical (NLO) property was evaluated using Z-scan measurement. The molecular electronic arrangement of Bn-BPY significantly affects the nonlinear absorption properties resulting into reverse saturable absorption (nonlinear absorption coefficient β = 0.256 × 10 m/W). In contrast, the Bn-BDY displays saturable absorption character. The calculated third-order nonlinear susceptibility χ value is 12.23 × 10 esu and 2.49 × 10 esu for Bn-BDY and Bn-BPY respectively. The power limiting behaviour of Bn-BPY displays limiting threshold energy around 70 Jcm with clamped output at ~35 Jcm.
分别在 4,4' 和 2,6 位带有苄基基团 (Bn) 的 BOPHY (BPY) 和 BODIPY (BDY) 染料被合成并进行了表征。进行了荧光衰减测量，结果表明苄基 BOPHY（Bn-BPY）的荧光寿命比苄基 BODIPY（Bn-BDY）短。在甲苯中，发现 Bn-BDY 和 Bn-BPY 的跃迁偶极矩分别为 6.93 和 11.3 D。分子静电势 (MEP) 图显示 Bn-BDY 比 Bn-BPY 更具极性。使用 Z 扫描测量评估了非线性光学 (NLO) 性质。Bn-BPY 的分子电子排列显著影响非线性吸收特性，导致反饱和吸收（非线性吸收系数 β=0.256×10 m/W）。相比之下，Bn-BDY 显示出饱和吸收特性。计算得到的三阶非线性磁化率 χ 值分别为 12.23×10 esu 和 2.49×10 esu，用于 Bn-BDY 和 Bn-BPY。Bn-BPY 的功率限制行为显示出约 70 Jcm 的限制阈值能量，在~35 Jcm 时具有夹紧输出。
