Temperature-dependent magnetic properties of 3 were performed between 300 -2 K. The measured T value at 300 K was 3.4 cm 3 mol -1 K, confirming the HS state of 3 with significant orbital contributions. Upon lowering the temperature, the T vs. T plot displays a three-step transition with the inflection points of 240, 160, and 100 K corresponding around 93%, 71%, and 25% of the HS Fe(II) in 3, respectively. T vs. T plot in the heating mode from 2 -300 K almost overlapped with the cooling mode without any hysteresis loop. Overall results confirmed a reversible three-step SCO in 3. The presence of competing opposite intra-or intermolecular short interactions and long-range elastic interactions in 3 might be responsible for such a three-step SCO (Fig. ).