We present a new formula and implementation for a descriptor enabling quantification of the electron–hole distance associated with a charge transfer of an optical transition, on the basis of the knowledge of the densities of the electronic ground and excited states. This index is able to define a charge-transfer length even for systems that would be otherwise difficult to treat, like symmetric molecules, while maintaining a very low computational cost and the possibility to be coupled to any method providing ground and excited state electron densities. After a benchmark of its performance on a series of push–pull molecules, the index has been applied to a set of large symmetric luminophores, the so-called “butterfly molecules”, showing promising applications in optoelectronics, to highlight its potential use in the design of new compounds.

中文翻译：

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基于一般密度的指数来分析电荷转移现象：从模型到蝴蝶分子。

我们基于对电子基态和激发态的密度的了解，为描述符提供了一个新的公式和实现方式，该描述符能够量化与光学跃迁的电荷转移相关的电子-空穴距离。即使对于原本难以处理的系统（如对称分子），该指数也能够定义电荷转移长度，同时保持非常低的计算成本，并有可能与提供基态和激发态电子密度的任何方法结合使用。在一系列推挽式分子的性能基准测试之后，该指数已应用于一组大型对称发光体（即所谓的“蝴蝶分子”），在光电子学中显示出广阔的应用前景，以突出其在光电子学中的潜在用途。新化合物的设计。