# The Raman fingerprint of rhombohedral graphite

## TL;DR

This paper provides a first-principles analysis of the 2D Raman spectrum in various multilayer graphene stackings, enabling non-destructive identification of rhombohedral graphite, which is crucial for exploring its potential correlated electronic states.

## Contribution

It offers the first theoretical description of the 2D Raman fingerprint in rhombohedral multilayer graphene and practical methods for its identification.

## Key findings

- First-principles Raman spectra for 3 and 4 layer graphene
- Identification protocols for ABC stacking sequences
- Enhanced understanding of Raman features in Bernal and rhombohedral graphite

## Abstract

Multi-layer graphene with rhombohedral stacking is a promising carbon phase possibly displaying correlated states like magnetism or superconductivity due to the occurrence of a flat surface band at the Fermi level. Recently, flakes of thickness up to 17 layers were tentatively attributed ABC sequences although the Raman fingerprint of rhombohedral multilayer graphene is currently unknown and the 2D resonant Raman spectrum of Bernal graphite not understood. We provide a first principles description of the 2D Raman peak in three and four layers graphene (all stackings) as well as in Bernal, rhombohedral and an alternation of Bernal and rhombohedral graphite. We give practical prescriptions to identify long range sequences of ABC multi-layer graphene. Our work is a prerequisite to experimental non-destructive identification and synthesis of rhombohedral graphite.