Besides ZFS parameters, the g tensor corresponding to a pair of KDs, which imparts the preferential direction of magnetization in a particular spin-orbit state, is an important parameter for governing the efficiency of SIMs. Complexes with g z > g y ≈ g x are characterized with easy axis anisotropy with g z as the favorable direction of magnetization. In contrast, g y ≈ g x > g z signifies easy plane anisotropy and g z > g y > g x represents the case of triaxial anisotropy. 55 The g tensors for the ground-state and the lowest three excited states of all the complexes are shown in Table . For complexes 1 and 4, the computed g tensors in the groundstate KDs are observed to show g z >> g y ≈ g x , indicating g z as the favorable direction of magnetization with strong Ising type nature. This uniaxial magnetic anisotropy signifies negligible relaxation of magnetization from the ground state Kramers pair. However, for the first and higher excited states, the extent of uniaxiality is reduced. Moreover, along with the changes in g, the direction of magnetization of the excited state from the ground state (measured as g z angle in Table ) also deviates. These decreased uniaxiality and noncoincidence of the anisotropy axis of excited state with respect to the ground-state leads to faster relaxation of magnetization from the corresponding state. For complexes 2 and 5, although the g-tensor show axiality with g z >> g y ≈ g x , but lacks pure Ising nature. This suggests partial tunneling within the ground state KDs along with faster tunneling through the excited state with reduced uniaxiality and deviation of anisotropy axis from the ground state. Complex 3 is a peculiar case possessing triaxial anisotropy with g z > g y > g x . This triaxial anisotropy has been observed earlier also for Co(II) compounds by Møller et al. and Korchagin et al.