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The large bridging ligand 9,10-anthracenedicarboxylate and its thiolated derivatives have been employed to assemble two dimolybdenum complex units and develop three Mo 2 dimers, [Mo 2 (DAniF) 3 ] 2 (μ-9,10-O 2 CC 14 H 8 CO 2 ), [Mo 2 (DAniF) 3 ] 2 (μ-9,10-OSCC 14 H 8 COS), and [Mo 2 (DAniF) 3 ] 2 (μ-9,10-S 2 CC 14 H 8 CS 2 ) (DAniF = N, N'-di( p-anisyl)formamidinate), for the study of conformation dependence of the electronic coupling between the two Mo 2 centers. These compounds feature a large deviation of the central anthracene ring from the plane defined by the Mo-Mo bond vectors, with the torsion angles (ϕ = 50-76°) increasing as the chelating atoms of the bridging ligand vary from O to S. Consequently, the corresponding mixed-valence complexes do not exhibit characteristic intervalence charge transfer absorptions in the near-IR spectra, in contrast to the phenylene and naphthalene analogues, from which these systems are assigned to the Class I in Robin-Day's scheme. Together with the phenylene and naphthalene series, the nine total mixed-valence complexes in three series complete a transition from the electronically uncoupled Class I to the strongly coupled Class II-III borderline via moderately coupled Class II and permit a systematic mapping of the bridge conformation effects on electronic coupling. Density functional theory calculations show that the HOMO-LUMO energy gap, corresponding to the metal (δ) to ligand (π*) transition energy, and the magnitude of HOMO-HOMO-1 splitting in energy are linearly related to cos 2 ϕ. Therefore, our experimental and theoretical results concur to indicate that the coupling strength decreases in the order of the bridging units: phenylene > naphthalene > anthracene, which verifies the through-bond superexchange mechanism for electronic coupling and electron transfer.