Space-filling Shapes the Interaction Networks in the Mixed Pyrrole–Benzene Trimer and Tetramer

Authors

• Simon Lobsiger, University of Virginia - Main Campus
• Zbigniew Kisiel, Polish Academy of Sciences
• Caroline S. Glick, Furman UniversityFollow
• George C. Shields, Furman UniversityFollow
• Brooks H. Pate, University of Virginia - Main CampusFollow
• Cristobal Perez, Universidade de Santiago de CompostelaFollow

ACS Citation

Lobsiger, S.; Kisiel, Z.; Glick, C.S.; Shields, G.C.; Pate, B.H.; Pérez, C. Space-filling Shapes the Interaction Networks in the Mixed Pyrrole–Benzene Trimer and Tetramer. Commun. Chem., 2026, 9, 213. DOI: 10.1038/s42004-026-02027-1

Version of Record

https://doi.org/10.1038/s42004-026-02027-1

Abstract

The structural preferences of molecular assemblies are governed by a delicate balance between strong directional forces and diffuse dispersion contacts. Mixed trimers of pyrrole (Py) and benzene (Bz) provide an ideal benchmark to probe this interplay: the robust N-H⋯π interaction anchoring the Py-Bz dimer competes with the drive toward compact, dispersion-stabilized arrangements in larger clusters. Here, we report the first high-resolution structural characterization of the Py-(Bz)2 and (Py)2-Bz trimers and the (Py)2-(Bz)2 tetramer using chirped-pulse Fourier transform microwave spectroscopy combined with dispersion-corrected DFT calculations and intensity-based cross-correlation analysis. The results show that while N-H⋯π and C-H⋯π interactions serve as primary anchors, the overall geometries are dictated by space-filling principles that maximize dispersion contacts. These findings establish pyrrole-benzene hetero clusters as a rigorous benchmark for theoretical methods and provide fundamental insight into the forces guiding aromatic aggregation and self-assembly in complex molecular systems.

Source Name

Communications Chemistry

Publication Date

Spring 4-17-2026

Volume

9

Page(s)

213

Document Type

Citation

Citation Type

Article

Disciplines

Chemistry