# Antibonding Ground state of Adatom Molecules in Bulk Dirac Semimetals

## TL;DR

This paper theoretically predicts that in 3D Dirac semimetals, two distant adatoms can have an antibonding ground state, reversing the usual energy order, and suggests an STM-based experiment to observe this phenomenon.

## Contribution

It introduces a novel antibonding ground state in adatom molecules within Dirac semimetals, challenging conventional bonding theories.

## Key findings

- Antibonding ground state can occur in adatom pairs in Dirac semimetals.
- Proposes an STM experiment to visualize the local density of states.
- Reverses the typical energy ordering of molecular states.

## Abstract

The ground state of the diatomic molecules in nature is inevitably bonding, and its first excited state is antibonding. We demonstrate theoretically that, for a pair of distant adatoms placed buried in three-dimensional-Dirac semimetals, this natural order of the states can be reversed and an antibonding ground state occurs at the lowest energy of the so-called bound states in the continuum. We propose an experimental protocol with the use of a scanning tunneling microscope tip to visualize the topographic map of the local density of states on the surface of the system to reveal the emerging physics.