Figure 1

Susceptibility of Heisenberg rings with $-J_1=J_2=8.2\mathrm{m}\mathrm{e}\mathrm{V}$, $J_{\mathrm{D}\mathrm{C}}=0$. $N=16$ sites, $g_L=2.24$ and 2.0, respectively, (full lines) compared with Ref. 1: $\square$ magnetic field $\mathbf{H}\parallel c$; $\circ$ $\mathbf{H}\parallel (a,b)$. Inset: the DC scenario [(a), [1]] compared with the single-chain scenario (b). Thick lines symbolize strong coupling. The empirical $J$’s are in accord with LDA and microscopic estimates [7]. Naturally, the finite cluster approach cannot describe the low-$T$ behavior of $\chi (T)$.Reuse & Permissions