We present recent results on the structure of the one-valence-particle 41 Ca and 49 Ca, and onevalence-hole 47 Ca, nuclei. The isotopes of interest were populated via the cold-neutron capture reactions 40 Ca(n,γ), 48 Ca(n,γ) and 46 Ca(n,γ), respectively. The experiments were performed at the Institut Laue-Langevin, within the EXILL campaign, which employed a large array of HPGe detectors. The γ decay and level schemes of these nuclei were investigated by γ-ray coincidence relationships, leading to the identification of 41, 10, and 6 new transitions in 41 Ca, 47 Ca, and 49 Ca, respectively. Branching ratios and intensities were extracted for the γ decay from each state, and γ-ray angular correlations were performed to establish a number of transition multipolarities and mixing ratios, thus helping in the spin assignment of the states. The experimental findings are discussed along with microscopic, self-consistent beyond-mean-field calculations performed with the Hybrid Configuration Mixing model, based on a Skyrme SkX Hamiltonian. The latter suggests that a fraction of the low-spin states of the 41 Ca, 49 Ca, and 47 Ca nuclei is characterized by the coexistence of either 2p-1h and 1p-2h excitations, or couplings between single-particle/hole degrees of freedom and collective vibrations (phonons) of the doubly-magic "core".