The synthesis, structure, and physical properties of a Heisenberg exchange-coupled cluster containing naphthalene groups are described. [Fe-2(O)(O2CCH2C10H7)(2)(TACN-Me-3)(2)](2+) (3) crystallizes in space group P (1) over bar with unit cell parameters a = 12.94(2) Angstrom, b = 14.84(2) Angstrom, c = 15.23(2) Angstrom, alpha = 101.12(7)degrees, beta = 90.8(1)degrees, gamma = 114.14(7)degrees, V = 2605(6) Angstrom(3), and Z = 2 with R = 0.0425 and wR2 = 0.1182. Variable-temperature magnetic susceptibility data indicate that the two high-spin Fe-III centers are antiferromagnetically coupled with J = -105 cm(-1) (H = -2JS(1).S-2), which is typical for this class of compounds. The room-temperature static emission spectrum of the compound in deoxygenated CH3CN solution is centered near 335 nm and has features reminiscent of both methyl-2-naphthylacetate (1) and [Zn-2(OH)(O2CCH2C10H7)(2)(TACN-Me-3)(2)](+) (2) with the following two caveats: (1) the overall emission intensity is roughly a factor of 10 less than that of the free ester (1, Phi(r) = 0.13) or the Zn-II analogue (2, Phi(r) = 0.14), and (2) there is significant broadening of the low-energy shoulder of the emission envelope. Time-correlated single photon counting data revealed biphasic emission for 3 with tau(1) = 4.6 +/- 1 ns and tau(2) = 47 +/- 1 ns. The latter compares favorably with that found for 2 (tau = 47 +/- 1 ns) and is assigned as the S-0 --> S-1 fluorescence of naphthalene. Emission anisotropy, time-gated emission spectra, and nanosecond time-resolved absorption measurements all support the assignment of the 4.6 ns component as being due to a singlet excimer that forms between the two naphthylacetate groups of 3, a process that is likely mediated by the structural constraints of the oxo-bis-carboxylato diiron core. No direct evidence for intramolecular electron and/or energy transfer from the photoexcited naphthyl group to the iron-oxo core was obtained, suggesting that the short-lived excimer may contribute to circumventing such pathways in this type of system.