Spin-split states in aromatic molecules and superconductors

TL;DR

This paper proposes that aromatic molecules and superconductors share a common ground state characterized by spin currents, offering a unified explanation for their magnetic properties and suggesting relevance to biological systems.

Contribution

It introduces a novel spin-current ground state model for aromatic molecules, extending the concept from superconductors and providing a natural explanation for their magnetic behaviors.

Findings

Exact diagonalization of a six-atom ring model shows a ground state with spin current.

The model explains large diamagnetic susceptibilities and NMR shifts in aromatic molecules.

Proposes relevance of spin-current states in biological matter.

Abstract

A state where spin currents exist in the absence of external fields has recently been proposed to describe the superconducting state of metals. It is proposed here that such a state also describes the ground state of aromatic molecules. It is argued that this point of view provides a more natural explanation for the large diamagnetic susceptibilities and NMR shifts observed in these molecules than the conventional viewpoint, and it provides a unified description of aromatic molecules and superconductors as sought by F. London. A six-atom ring model is solved by exact diagonalization and parameters in the model where a ground state spin current exists are found. We suggest that this physics plays a key role in biological matter.