“…20 The O axis -Co1-O axis (180°) and N axis -Co2-N axis (180°) axial angles are linear, which means that no appreciable distortion in the Z axis is observed and indicates that such a d 7 octahedral complex has a high-spin system. 21 In 1, each (R,S)-bpdado ligand employs a tridentate coordination mode to link three metal Co centers (two Co1 and one Co2) by utilizing two carboxylic groups and two N-oxide CrystEngComm Paper groups (Table 1a). Two N-oxide atoms connect one Co2 in the bis-chelating mode to generate a seven-membered ring, and each carboxylic group, adopting a μ 1 -η 1 :η 0 bridging mode, connects a Co1 atom to generate a ijCo1IJR-bpdado)] n or ijCo1IJS-bpdado)] n helical chain, namely, a left-or right-handed helix propagating along the c axis with a 2 1 screw axis and a pitch of 7.489(9) Å (Fig.…”