Phase transitions and thermodynamics of the two-dimensional Ising model on a distorted Kagom\'{e} lattice

TL;DR

This paper investigates the phase transitions and thermodynamic properties of the two-dimensional Ising model on a distorted Kagomé lattice using exact solutions and tensor renormalisation group methods, revealing phase diagrams, critical behavior, and fitting experimental susceptibility data.

Contribution

It provides the first detailed phase diagram and thermodynamic analysis of the Ising model on a distorted Kagomé lattice using combined exact and TRG methods, including experimental data fitting.

Findings

Identified ferromagnetic, ferrimagnetic, and paramagnetic phases with second-order transitions.

Observed magnetization plateaux at m=1/3 in certain couplings.

Fitted experimental susceptibility data with theoretical results, estimating coupling constants.

Abstract

The two-dimensional Ising model on a distorted Kagom\'{e} lattice is studied by means of exact solutions and the tensor renormalisation group (TRG) method. The zero-field phase diagrams are obtained, where three phases such as ferromagnetic, ferrimagnetic and paramagnetic phases, along with the second-order phase transitions, have been identified. The TRG results are quite accurate and reliable in comparison to the exact solutions. In a magnetic field, the magnetization ($m$), susceptibility and specific heat are studied by the TRG algorithm, where the $m=1/3$ plateaux are observed in the magnetization curves for some couplings. The experimental data of susceptibility for the complex Co(N$_3$)$_2$(bpg)$\cdot$ DMF$_{4/3}$ are fitted with the TRG results, giving the couplings of the complex $J=22K$ and $J'=33K$.