Figure 2
From: Two coupled chains are simpler than one: field-induced chirality in a frustrated spin ladder
Crystal structure of BiCu\(_2\)PO\(_6\). The positions27 of Cu (light and dark blue), P (gray) and Bi (purple) are shown; O sites have been omitted for clarity. Exchange interactions1 (\(J_1\), \(J_2^\prime\), \(J_2\), \(J_\perp\), and \(J_i\)) are depicted by blue (intraladder couplings) and black (interladder couplings) lines. (a) View along b, illustrating the two ladder orientations. Dashed lines mark one ladder layer. (b) Two ladder units. Hyperfine couplings28 between \(^{31}\)P nuclei and Cu sites are represented by gray pyramids. (c) Single ladder. Magenta arrows in (a) and (c) illustrate the staggering of the transverse and parallel components, \(D_1^{ac}\) and \(D_1^b\), of the DM vectors29,30,31 on the nearest-neighbor bonds [projected into bc plane in (c)]. Illustrations created using VESTA32.
