# Multiconfigurational Ground State of a Diradicaloid Characterized at the Atomic Scale

## TL;DR

Scientists used advanced microscopy to observe and characterize a complex molecule's electronic structure at the atomic level.

## Contribution

The study experimentally demonstrates strong electronic correlations in a single molecule's ground state.

## Key findings

- The molecule's bond-order contrast was measured using atomic force microscopy.
- Charge-state transitions were mapped via scanning tunneling microscopy.
- Multiconfigurational calculations confirmed a many-body ground state.

## Abstract

We report the tip-induced generation and scanning probe
characterization
of a singlet diradicaloid, consisting of two phenalenyl units connected
by an sp-hybridized C4 chain on an ultrathin insulating
NaCl surface. The bond-order contrast along the C4 chain
measured by atomic force microscopy and mapping of charge-state transitions
by scanning tunneling microscopy, in conjunction with multiconfigurational
calculations, reveal that the molecule exhibits a many-body ground
state. Our study experimentally demonstrates the manifestation of
strong electronic correlations in the geometric and electronic structures
of a single molecule.