Green Ori, Gajst Oren, Simkovitch Ron, Shabat Doron, Huppert Dan
Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University , Tel Aviv 69978, Israel.
J Phys Chem A. 2017 Apr 27;121(16):3079-3087. doi: 10.1021/acs.jpca.7b02490. Epub 2017 Apr 13.
Steady-state and time-resolved fluorescence techniques were employed to study the excited-state proton transfer (ESPT) to water and DO of a new photoacid, phenol benzoate cyanine picolinium salt (BCyP). We found that the ground-state pK is about 6.5, whereas the excited-state pK* is about -4.5. The ESPT rate constant, k, to water is ∼0.5 × 10s (τ ≈ 2 ps) and in DO the rate is 0.33 × 10 s. We determined that the BCyP photoacid belongs to the third regime of photoacids, the solvent-controlled regime.
采用稳态和时间分辨荧光技术研究了一种新型光酸——苯酚苯甲酸氰基吡啶盐（BCyP）向水和重水的激发态质子转移（ESPT）。我们发现基态pK约为6.5，而激发态pK*约为 -4.5。向水的ESPT速率常数k约为0.5×10⁹ s⁻¹（τ≈2 ps），在重水中速率为0.33×10⁹ s⁻¹。我们确定BCyP光酸属于光酸的第三种类型，即溶剂控制型。
