共价键合双金属D-B-A模型分子的合成及其电子偶合与电子传递研究

Based on covalently bonded dimetal coordination units, series of novel symmetrical and unsymmetrical D-B-A model complexes will be designed and synthesized. Under the contemporary theoretical framework, this program will focus on, by taking theoretical and experimental approaches, the following aspects: 1)the charge distribution on the mixed-valence cation radicals and the degree of electronic delocalization; 2)the Classes that the mixed-valence compounds belong to, and the existence and spectroscopic behavior of the transition state between Class II and Class III; 3)the determination and the controlling strategies of the intrinsic potential difference in unsymmetrical complexes; 4)kinetics and mechanism for the electron transfer reactions. Through the research in this project, synthetic methods for symmetrical and unsymmetrical systems will be optimized , better understanding on the strategy achieved and experimental approaches in controlling the metal to metal electronic coupling interaction explored. By study of various complexes, the Hush two-state model and the CNS superexchange formalism will be tested for their consistency, on this basis, providing the latest CNS theory with experimental support. By taking advantage of the molecular and electronic structural features, along with the applications of Marcus and Marcus-Hush theories, we are able to evaluate the related theoretical models with reasonable data, in hope of gaining additional knowledge on the fundamentals of electronic coupling and electron transfer.

本项目拟基于共价键合双金属配位单元，设计合成系列新的、对称和不对称的D-B-A模型化合物，在现有理论框架范围，从实验和理论两方面研究探讨：1）混价阳离子自由基中电荷分布情况和电子离域程度；2）混价化合物的所属类别以及Class II-Class III 过渡态的存在形式和谱学特征；3）不对称体系电子给、受体间电位差的物理化学测定方法和调控策略；4）电子转移反应动力学和机理。通过此项目研究工作，进一步完善对称和不对称的M2-M2分子的合成方法，掌握调控金属到金属电子偶合作用的一般策略和实验途径。在不同化合物体系，验证Hush双态模型和CNS超交换理论计算结果的一致性，在此基础上，给予新的CNS理论以实验上的支持。利用M2-M2体系分子结构和电子性质的特点，通过Marcus和Marcus-Hush理论的应用，以各种参数、变量的合理性评价相关理论模型，促进现有电子偶合和电子转移基础理论的发展。

本项目基于共价键合双金属配位单元与各类配体组装，设计合成了系列新的、对称和不对称的键合双钼体系D-B-A模型化合物，从实验和理论两方面进行了研究探讨：研究了配位原子、辅助配体、桥配体的长度以及立体结构等对电子转移的影响； 确定了混价化合物的所属类别以及Class II-Class III 过渡态的存在形式和谱学特征；掌握了不对称体系电子给、受体间电位差的物理化学测定方法和调控策略。通过对这些体系的研究，进一步完善了对称和不对称的M2-M2分子的合成方法，掌握了调控金属到金属电子偶合作用的一般策略和实验途径。并在不同化合物体系，验证了Hush双态模型和CNS超交换理论计算结果的一致性，促进了现有电子偶合和电子转移基础理论的发展。