Numerical simulation of a device with two spin crossover complexes: application for temperature and pressure sensors

Jorge Linares,Salah Eddine Allal,Yann Garcia,Pierre Richard Dahoo

doi:10.1088/1742-6596/936/1/012048

Abstract

The spin-crossover (SCO) phenomenon is related to the ability of a transition metal to change its spin state vs. a given perturbation. For an iron(II) SCO complexes the reversible changes involve the diamagnetic low-spin (S = 0) and the paramagnetic high-spin (HS S = 2) states [1,2,3]. In this contribution we simulate the HS Fraction (nHS) for different set values of temperature and pressure for a device using two SCO complexes with weak elastic interactions. We improve the calculation given by Linares et al. [4], taking also into account different volume (VHS, VLS) changes of the SCO. We perform all the calculation in the frame work of an Ising-like model solved in the mean-field approximation. The two SCO show in the case of “weak elastic interactions”, gradual spin transitions such that both temperature and pressure values can be obtained from the optical observation in the light of calculations discussed in this article.

Highlights

The increasing demand regarding safety and security rules require applications that involve advanced sensors with higher sensitivity, better technical specifications, lower dimensions and low energy consumption
In this work we show that spin crossover (SCO) compounds can be used as a visual detector of strong mechanical contact pressure and temperature
Published under licence by IOP Publishing Ltd reflectivity measurements, a correlation of the optical SCO properties with the pressure contact and temperature highlighted thanks to an Ising-like model. These results provide the basis for the construction of a thermal and pressure sensor

Summary

Introduction

The increasing demand regarding safety and security rules require applications that involve advanced sensors with higher sensitivity, better technical specifications, lower dimensions and low energy consumption. Interesting properties that could be used in these applications are exhibited by spin crossover (SCO) molecular materials [1,2,3]. In this work we show that SCO compounds can be used as a visual detector of strong mechanical contact pressure and temperature.

Results

Conclusion