<p>Molecular bistability and multistability is a key characteristic which can be used in functional materials applied in prospective nano- and molecular electronic devices such as switches, diodes, and photovoltaics. The desired performance of such molecular devices depends on the electronic properties of the interconverting electronic/bonding states under diverse stimuli conditions, which can be tuned, e.g., by varying substitutions and changing the engaged transition metal ions and their coordination structures. In the present work, bistability due to intramolecular charge transfer (IMCT) between the two [Co] and [Fe] coordination subsystems of the mixed-valence heterometallic binuclear complex [(SeCN–)₂(bpym)Co^II/III(–bpym–)-Fe^III/II(bpym)(–NCSe)₂]⁺, corresponding to the interconversion of its two oxidation states [Co^II–Fe^III] and [Co^III–Fe^II], is proved computationally using DFT-UB3LYP/cc-pVDZ[LANL2DZ] method. The transition state (<i>TS</i>) structure of this IMCT switching reaction is located and characterized and the intrinsic reaction coordinate (IRC) is derived by searching potential energy hypersurface along the switching path from the <i>TS</i> structure in the forward and reverse directions. The derived IRC showed that the IMCT switching has only one <i>TS</i> which has a single negative mode of 17.02<i>i</i> cm^‒1 with forward ([Co^II–Fe^III] → [Co^III–Fe^II]) and reverse ([Co^II–Fe^III] ← [Co^III–Fe^II]) activation energies of 13.1 and 27.9&#xa0;kJ/mol, respectively. These activation energies denote that infrared radiation can be used to actuate the switching function between the two [Co^II–Fe^III] and [Co^III–Fe^II] oxidation states of this binuclear complex. Analysis of the atomic/group electric charges of the two [Co] and [Fe] coordination subsystems of this bistable cobalt–iron complex showed that the IMCT in this system corresponds to polarization switching.</p> Graphical abstract <p></p>