Sekhosana Kutloano E, Nyokong Tebello
Institute for Nanotechnology and Innovation, Department of Chemistry, Rhodes University PO Box 94 Grahamstown 6140 South Africa
RSC Adv. 2019 May 23;9(28):16223-16234. doi: 10.1039/c9ra01836k. eCollection 2019 May 20.
The coordination system of rare-earth n-tuple decker phthalocyanines would be better suited with appropriate metal ions with the correct coordination number and the solvent system of the reaction, amongst other reasons, for the formation of n-tuple decker phthalocyanines. As a result, these complexes are very rare. In this manuscript, we present new n-tuple decker phthalocyanines in the form of double- (complex 2), quadruple- (complex 3a) and sextuple-decker phthalocyanines (complex 3b), all of which contain neodymium and cadmium metal ions. The primary focus is the investigation of the nonlinear optical (NLO) mechanisms responsible for the observed reverse saturable absorption. While the extension of the π-electron system has been found to enhance the nonlinear optical behavior of complexes 3a and 3b, a change in the NLO mechanisms has been observed, with complex 2 lacking the triplet state population, as revealed by a laser flash photolysis technique. It has also been established that the excited state absorption cross sections follow a clear order of magnitude for the complexes under investigation: (for 3b) > (for 3a) > (for 2). This trend evidences the effects of the extension of the π-electron system.
稀土 n 重夹心酞菁的配位体系，除其他因素外，若能与具有正确配位数的合适金属离子以及反应的溶剂体系相匹配，则更有利于 n 重夹心酞菁的形成。因此，这些配合物非常罕见。在本论文中，我们展示了新型的 n 重夹心酞菁，包括二重（配合物 2）、四重（配合物 3a）和六重夹心酞菁（配合物 3b），它们均含有钕和镉金属离子。主要重点是研究导致观察到的反饱和吸收的非线性光学（NLO）机制。虽然已发现 π 电子体系的扩展增强了配合物 3a 和 3b 的非线性光学行为，但观察到 NLO 机制发生了变化，激光闪光光解技术表明配合物 2 缺乏三重态布居。还已确定，对于所研究的配合物，激发态吸收截面遵循明确的量级顺序：（对于 3b）> （对于 3a）> （对于 2）。这种趋势证明了 π 电子体系扩展的影响。
