Photophysical behavior of open-shell first-row transition-metal octabutoxynaphthalocyanines:: CoNc(OBu)8 and CuNc(OBu)8 as case studies
Photophysical behavior of open-shell first-row transition-metal octabutoxynaphthalocyanines:: CoNc(OBu)8 and CuNc(OBu)8 as case studies
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DOI：
10.1021/ic7023204
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发表时间：
2008-05-19
影响因子：
4.6
通讯作者：
Rodgers, Michael A. J.
中科院分区：
文献类型：
--
作者：
Soldatova, Alexandra V.;Kim, Junhwan;Rodgers, Michael A. J.
报道了Co和Cu与5、9、14、18、23、27、32、36-八磺酰基酞菁[CoNc(OBu)(8)和CuNc(OBu)(8)]配合物的超快光动力学和密度泛函理论/时变密度泛函理论（DFT/TDDFT）结果。在此基础上，详细介绍了这些配合物的合成及相应的Zn配合物（作为参考）。采用飞秒时间分辨率的瞬态吸收光谱法结合详细的DFT/TDDFT分析，构建了Co和Cu配合物在q波段激发后的激发态动力学的完整图像，并了解了金属中心性质与激发态寿命之间的关系。Co配合物通过两个相互竞争的通道返回基态：T-2(1)（pi, pi*）状态衰减，寿命为1ps，低能级(2)（d, d）状态重新填充基态表面，寿命为15ps。CuNc (OBu)(8)显示，基态从T-2(1)（pi, pi*）状态通过低能级配体到金属的电荷转移（LMCT）状态重新填充，该状态在几纳秒内完成。将钴和铜配合物的光物理行为与先前报道的镍类似物进行比较，以突出中心金属对失活途径的性质和速率的影响。在这项工作中描述的结果提供了基本的知识，是相关的使用这些化合物作为光热增敏剂在癌症治疗。
Ultrafast photodynamics and density functional theory/time-dependent density functional theory (DFT/TDDFT) results for complexes of Co and Cu with 5,9,14,18,23,27,32,36-octabutoxynaphthalocyanine [CoNc(OBu)(8) and CuNc(OBu)(8)] are reported. As a basis for this work, details concerning the syntheses of these complexes and the corresponding Zn complex (used as a reference) are given. Transient absorption spectrometry with femtosecond time resolution combined with a detailed DFT/TDDFT analysis has been employed to construct a complete picture of the excited-state dynamics after Q-band excitation of the Co and Cu complexes and to gain an understanding of the relationship between the nature of the metal center and the excited-state lifetime. The Co complex was shown to return to its ground state via two competing channels: a T-2(1)(pi, pi*) state that decayed with a lifetime of 1 ps and a low-lying (2)(d, d) state that repopulated the ground-state surface with a lifetime of 15 ps. CuNc (OBu)(8) showed ground-state repopulation from the T-2(1)(pi, pi*) state via a lower-lying ligand-to-metal charge-transfer (LMCT) state that was completed within a few nanoseconds. The photophysical behavior of the cobalt and copper complexes was compared to that previously reported for the nickel analog in an effort to highlight the effect of the central metal on the nature and rates of the deactivation pathways. The results described in this work provide basic knowledge that is relevant to the use of these compounds as photothermal sensitizers in cancer therapy.