The magnetic behaviour of azurite

Magnetoelastic couplings in the distorted diamond-chain compound azurite

“…The observation of a plateau at 1/3 of the saturation magnetization [9] is consistent with a description of azurite in terms of an alternating dimer-monomer model [2,10]. Two characteristic temperatures (energies) have been derived from peaks in the magnetic susceptibility χ (T ) [9,10]. Whereas the peak at T χ 1 25 K has been assigned to the dominant intradimer coupling J 2 , the one at T χ 2 5 K has been linked to a monomer-monomer coupling along the chain b axis [9].…”

“…In recent years, great interest has surrounded the discovery of azurite, Cu 3 (CO 3 ) 2 (OH) 2 [5], as a model system of a Cu 2+ (S = 1/2)-based distorted diamond chain with J 1 = J 2 =J 3 [9]. The observation of a plateau at 1/3 of the saturation magnetization [9] is consistent with a description of azurite in terms of an alternating dimer-monomer model [2,10]. Two characteristic temperatures (energies) have been derived from peaks in the magnetic susceptibility χ (T ) [9,10].…”

“…We assign these features [labeled T c 22 1 and T c 22 2 in the inset to Fig. 1(a)] to the characteristic temperatures T 1 and T 2 of azurite, as revealed by susceptibility measurements [9,10]. In addition, the elastic data highlight a sharp minimum around 1.9 K, reflecting the transition into long-range antiferromagnetic ordering at T N = 1.88 K, and a steplike softening of comparable size to that at T N around T 0 = 0.37 K. The latter feature is likely to be of magnetic origin as well [24].…”

Dynamics of azurite Cu3(CO3)2(OH)Rule1, Tennant2, Caux3 et al. 2011Phys. Rev. B202220View full textAdd to dashboardCite

“…Much experimental analysis and theoretical modeling have been performed however there is as yet no general consensus as to the exact magnitudes of the exchange interactions either within the 1D diamond chain, or between chains [1][2][3][4]6 . Despite this, there is significant evidence that suggests the exchange interaction J 2 is by far the strongest interaction leading to a coupling of Cu-ions into dimers and monomers 2,4,11 . From these results it is now widely believed that azurite cannot be described in terms of a simple isotropic exchange chain Hamiltonian, but rather that inter-chain coupling and/or anisotropic exchange must also be taken into ac-count when describing this material.…”

Magnetic and crystal structure of azurite Cu3(CO3)<

“…Interest in the magnetic properties of this material began in the 1950s when an ordered antiferromagnetic (AFM) ground state was observed below 1.9 K. 1,2 From these studies, a detailed description of the magnetic moment structure was never revealed however it has been speculated that the low ordering temperature may result from frustration in the diamond arrangement of spin-1/2 Cu 2+ ions 3 . Early susceptibility measurements indicated that the coupling of spins within the chain could be described with alternating dimers and monomers 4 ( Fig. 1).…”