Magnetic birefringence of a ferromagnetic linear chain CuCl2⋅TMSO

Abstract

Copper chloride monoTMSO has previously been shown to be an example of a spin-1/2 linear chain with Heisenberg ferromagnetic exchange (J/k≊39 K). Motivated by the proportionality between the temperature derivative of the linear magnetic birefringence (TDLMB) and the magnetic specific heat, we have determined the birefringence of the title compound along the 010 and 100 faces between 3.1 and 260 K. The data along the 010 face show no evidence of magnetic behavior. They could be fit to a Debye function with a θD of 123 K. Along the 100 face, a sharp spike was seen at 3.42 K, indicating the transition to long-range magnetic order. The data for the 100 face could not be fit to a Debye function alone but were successfully modeled as a sum of a lattice contribution (θD ≊244 K) and a ferromagnetic contribution with an exchange constant J/k between 30 and 60 K. The data was insensitive to the magnitude of J.

Magnetic birefringence of two S=1/2 Heisenberg antiferromagnetic chains

“…7 Attempts to improve the fit to the CDB (010) data by adding a Debye term to the theoretical expression were unsuccessful. 7 Attempts to improve the fit to the CDB (010) data by adding a Debye term to the theoretical expression were unsuccessful.…”

Precision Determination of Exchange Strengths in Magnetic Dimers via Birefringence

“…The compounds chosen for study were A flow-type helium cryostat has been used to very the sample temperature between 3.5 and 250 K. The TDLB was determined using an arrangement in which the sample, Soleil-Babinet compensator and a photoelastic modulator are placed between crossed polarizers [5]. An arc lamp/monochromator combination was used as a light source (A = 543 nm) .…”