The N-14 nuclear quadrupole coupling (NQC) constants (chi) and asymmetry parameters (eta) for a series of small nitrogen-containing imidazole derivatives are investigated, by using density functional theory (DFT), in three clearly distinct environments: as free molecules, in the solid state, and in solution. The spectroscopic characterization is also extended to coenzyme B-12 and cob(II)alamin systems. The main findings can be summarized as follows: (i) Deviations in the calculated chi for the two nitrogen sites in the free imidazole molecule are small enough to allow quantitatively accurate predictions for isolated molecules of substituted benzimidazole compounds. (ii) Asymmetry parameters, however, are difficult to reproduce with accuracy; only trends along a Series of compounds can be taken as informative. (iii) Shifts of the NQC parameters on going from gas phase to solid state are reasonably well reproduced at a qualitative level by using a trimer model; to reach similar levels of accuracy in the case of eta, both the continuum and the point-charge effects need to be included. (iv) Short-range effects play an important role in the N-14 NQC parameters of imidazole in solution, although the NQC constants are also sensitive to solvent molecules beyond the first shell. (v) Long-range effects taken into account by an averaged continuum model alone are not enough to reproduce the effect of hydrogen bonding with-water on the N-14 NQC parameters of imidazole; whenever water molecules are present, these solvent molecules have to be included explicitly. (vi) Metal-ligand interactions are relevant only for the NQC parameters of the proximal N, more specifically for the eta value of this atom; most of the environmental effects in the real coenzymes are handled correctly by employing a solvated nonmetallic model. (viii) We estimate that the chi and eta for the proximal nitrogen atom in cob(II)alamin (which so far has escaped experimental observation) will be approximately 2.7 MHz and 0.8, respectively, as indicated by our calculations.