• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Chemistry: A European journal >Tetrathiafulvalene-Based Mixed-Valence Acceptor-Donor-Acceptor Triads: A Joint Theoretical and Experimental Approach
【24h】

Tetrathiafulvalene-Based Mixed-Valence Acceptor-Donor-Acceptor Triads: A Joint Theoretical and Experimental Approach

机译：基于四硫富瓦烯的混合价受体-供体-受体三元组：联合的理论和实验方法。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

This work presents a joint theoretical and experimental characterisation of the structural and electronic properties of two tetrathiafulvalene (TTF)-based acceptor-donor-acceptor triads (BQ-TTF-BQ and BTCNQ-TTF-BTCNQ; BQ is naphthoquinone and BTCNQ is benzotetracyano-p-quinodimethane) in their neutral and reduced states. The study is performed with the use of electrochemical, electron paramagnetic resonance (EPR), and UV/Vis/NIR spectroelectrochemical techniques guided by quantumchemical calculations. Emphasis is placed on the mixed-valence properties of both triads in their radical anion states. The electrochemical and EPR results reveal that both BQ-TTF-BQ and BTCNQ-TTF-BTCNQ triads in their radical anion states behave as class-II mixed-valence compounds with significant electronic communication between the acceptor moieties. Density functional theory calculations (BLYP35/cc-pVTZ), taking into account the solvent effects, predict charge-localised species (BQ·--TTF-BQ and BTCNQCé-TTF-BTCNQ) as the most stable structures for the radical anion states of both triads. A stronger localisation is found both experimentally and theoretically for the BTCNQ-TTF-BTCNQ anion, in accordance with the more electron-withdrawing character of the BTCNQ acceptor. CASSCF/CASPT2 calculations suggest that the low-energy, broad absorption bands observed experimentally for the BQ-TTF-BQ and BTCNQ-TTF-BTCNQ radical anions are associated with the intervalence charge transfer (IV-CT) electronic transition and two nearby donor-to-acceptor CT excitations. The study highlights the molecular efficiency of the electrondonor TTF unit as a molecular wire connecting two acceptor redox centres.
机译：这项工作提出了两个基于四硫富富瓦烯（TTF）的受体-供体-受体三联体（BQ-TTF-BQ和BTCNQ-TTF-BTCNQ; BQ是萘醌而BTCNQ是苯并四氰基-对喹啉甲烷）处于中性和还原状态。这项研究是使用电化学，电子顺磁共振（EPR）和以量子化学计算为指导的UV / Vis / NIR光谱电化学技术进行的。重点放在两个三元组在其自由基阴离子状态下的混合价性质。电化学和EPR结果表明，处于自由基阴离子状态的BQ-TTF-BQ和BTCNQ-TTF-BTCNQ三联体均表现为II类混合价化合物，在受体部分之间具有明显的电子连通。考虑溶剂效应的密度泛函理论计算（BLYP35 / cc-pVTZ），预测电荷局部化的物种（BQ·-TTF-BQ和BTCNQCé-TTF-BTCNQ）是最稳定的结构自由基阴离子状态两个黑社会。根据BTCNQ受体更具吸电子特性，在实验和理论上都发现BTCNQ-TTF-BTCNQ阴离子具有更强的定位性。 CASSCF / CASPT2计算表明，BQ-TTF-BQ和BTCNQ-TTF-BTCNQ自由基阴离子的实验观察到的低能宽吸收带与间隔电荷转移（IV-CT）电子跃迁和两个附近的供体-接受CT激发。该研究强调了电子给体TTF单元作为连接两个受体氧化还原中心的分子线的分子效率。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号