Spin 3/2 dimer model

TL;DR

This paper introduces a parent Hamiltonian for weakly dimerized valence bond solid states applicable to any half-integer spin, extending known models and analyzing its properties for spin 3/2, with implications for understanding dimerization phenomena.

Contribution

It provides a generalized Hamiltonian for half-integer spins, including explicit construction and analysis for spin 3/2, expanding the theoretical framework for dimerized spin chains.

Findings

Reduces to Majumdar-Ghosh model for S=1/2

Describes impurity-induced dimer phase in Cr8Ni

Applicable to arbitrary half-integer spins

Abstract

We present a parent Hamiltonian for weakly dimerized valence bond solid states for arbitrary half-integral S. While the model reduces for S=1/2 to the Majumdar-Ghosh Hamiltonian we discuss this model and its properties for S=3/2. Its degenerate ground state is the most popular toy model state for discussing dimerization in spin 3/2 chains. In particular, it describes the impurity induced dimer phase in Cr8Ni as proposed recently. We point out that the explicit construction of the Hamiltonian and its main features apply to arbitrary half-integral spin S.