Effect of S?π interactions on the charge transport properties of the DPP framework

作者：Wang, Xu; Hu, Zhonghao; Liang, Lei; Wang, Zhiye; Wang, Yanze; Li, Yunchuan^*; Xiao, Bohuai^*

来源：Chemical Communications, 2024, 60(7).

DOI：10.1039/d3cc04995g

• MOLECULE
• CONDUCTANCE

In this work, we designed and synthesized two similar pi-conjugated molecules, N-alkyl (DPP-R) and N-aryl (DPP-B), to comparatively explore the SMIDLINE HORIZONTAL ELLIPSIS pi interactions using a scanning tunneling microscopy-based break junction (STM-BJ) technique. The conductance results of the STM-BJ experiments indicated that DPP-R has a 66% greater conductance (G) than DPP-B. Combined with molecular simulations, it was demonstrated that the presence of SMIDLINE HORIZONTAL ELLIPSIS pi interactions led to a certain degree of orbital overlap of the highest occupied molecular orbital (HOMO), and created a favorable channel for electron transport in the DPP-B junction. @@@ We find that the SMIDLINE HORIZONTAL ELLIPSIS pi interactions can form a new through-space channel that favors charge transport and consequently improves the electronic properties in DPP derivatives.