C15H10Pt-Polymers and Nanobelts-XiaoNi-JMM-2026

Using the newly reported perfect in-plane [55555] metallo-annulene D5h Pt©C15H10 (1) (Zhao et al., Eur. J. Inorg.  Chem. 2025, 28, e202500420) as building blocks via partial dehydrogenations and based on extensive density functional theory calculations, we predict herein their stable conjugated planar polymers (Pt©C15)nH6n+4 (n=2–9) (2–9) and (Pt©C15H6)10 (10), non-metal sandwich complexes C2(Pt©C15H10)2 (1′), [C2(Pt©C15)2]nH2(6n+4) (n=2–9) (2′-9′), and [C2(Pt©C15H6)2]10 (10′), and tubular nanobelts (Pt©C15H6CH2)n (n=8, 10, 12) (11, 12, 13). Detailed adaptive natural density partitioning  (AdNDP) analyses indicate that the [55555] metallo-annulene polymers (Pt©C15)nH6n+4 (2–9) and (Pt©C15H6)10 (10) consist  of conjugated π-aromatic Pt©C15 building blocks interconnected by C6 hexagonal units, non-metal bis([55555] metalloannulene) sandwich complexes [C2(Pt©C15)2]nH2(6n+4) (2′-9′) and [C2(Pt©C15H6)2]10 (10′) contain n -C≡C- non-metal  coordination centers each sandwiched between two aromatic Pt©C15 ligands, while the tubular [55555] metallo-annulene  nanobelts (Pt©C15H6CH2)n (11, 12, 13) possess n conjugated π-aromatic Pt©C15 building blocks interlinked by n> CH2 carbene bridges. Bowl-shaped C5v M©C40H15 (M=Au, Ag, Cu) (14) and their metal sandwich complexes D5h Cr5(M©C40H15)2 (14′) are also proposed. The IR, Raman, and UV–vis spectra of the concerned species are theoretically simulated to facilitate  their experimental characterizations.