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Two heteroleptic Ni^II complexes combined the redox-active catecholate and 2,2′- bipyridine ligand platforms were synthesized to observe a photoinduced intramolecular ligand-to-ligand charge transfer (LL’CT, HOMO_catecholate → LUMO_α-diimine). A molecular design of compound [Ni^II(3,6-Cat)(bipy)]∙CH₃CN (<b>1</b>) on the base of bulky 3,6-di-<i>tert</i>-butyl-<i>o</i>-benzoquinone (<b>3,6-DTBQ</b>) was an annelation of the ligand with an electron donor glycol fragment, producing derivative [Ni^II(3,6-Cat^gly)(bipy)]∙CH₂Cl₂ (<b>2</b>), in order to influence the energy of LL’CT transition. A substantial longwave shift of the absorption peak was observed in the UV-Vis-NIR spectra of <b>2</b> compared with those in <b>1</b>. In addition, the studied Ni^II derivatives demonstrated a pronounced negative solvatochromism, which was established using a broad set of solvents. The molecular geometry of both compounds can be ascribed as an insignificantly distorted square-planar type, and the π–π intermolecular stacking of the neighboring α-diimines is realized in a crystal packing. There is a lamellar crystal structure for complex <b>1</b>, whereas the perpendicular T-motifs with the inter-stacks attractive π–π interactions form the packing of complex <b>2</b>. The redox-active nature of ligand systems was clearly shown through the electrochemical study: a quasi-reversible one-electron reduction of 2,2′-bipyridine and two reversible successive one-electron oxidative conversations (“catecholate dianion—<i>o</i>-benzosemiquinonato radical anion—neutral <i>o</i>-benzoquinone”) were detected.