We have examined the antiferromagneticly coupled bis(mu-oxo)dimanganese(IV) complex [Mn2O2(salpn)(2)] (1) with Mn-55 solid-state NMR at cryogenic temperatures and first-principle theory. The extracted values of the Mn-55 quadrupole coupling constant, C-Q, and its asymmetry parameter, eta(Q), for 1 are 24.7 MHz and 0.43, respectively. Further, there was a large anisotropic contribution to the shielding of each Mn4+, i.e. a Delta sigma of 3375 ppm. Utilizing broken symmetry density functional theory, the predicted values of the electric field gradient (EFG) or equivalently the C-Q and eta(Q) at ZORA, PBE QZ4P all electron level of theory are 23.4 MHz and 0.68, respectively, in good agreement with experimental observations.