Lattice-Directed Selective Synthesis of Acetylenic and Diacetylenic Organometallic Polyynes

As a bottom-up strategy, on-surface synthesis shows great potential in constructing novel carbon-based nanostructures. Herein, on-surface reactions of 1,1,2,2-tetraiodoethylene and 1,1,4,4-tetrabromo-1,2,3-butatriene were systematically explored. A combination of scanning tunneling microscopy and noncontact atomic force microscopy demonstrates that it is feasible to achieve acetylenic and diacetylenic organometallic polyyne (i.e., acetylenic Ag-carbyne and diacetylenic Cu-carbyne) on Ag(110) and Cu(110) surfaces, respectively. Interestingly, after annealing the sample, the acetylenic Ag-carbyne was transformed to diacetylenic Ag-carbyne on Ag(110), while an opposite transformation process occurred between diacetylenic and acetylenic Cu-carbyne on Cu(110). The DFT calculations indicate that such a lattice dependence of skeleton reconstruction originates from the thermodynamic stability of diacetylenic Ag-carbyne/acetylenic Cu-carbyne on the corresponding surfaces.

Automated summary

On-surface synthesis is a promising strategy for constructing novel carbon-based nanostructures. In this study, the on-surface reactions of 1,1,2,2-tetraiodoethylene and 1,1,4,4-tetrabromo-1,2,3-butatriene were systematically explored. The results showed the feasibility of achieving acetylenic and diacetylenic organometallic polyyne on Ag(110) and Cu(110) surfaces, respectively. The transformation between different structures after annealing indicated a lattice dependence of skeleton reconstruction on the corresponding surfaces.