<p dir="ltr">Transition metal complexes with redox-active ligands are foundational to many biological and synthetic transformations, enabling multielectron redox processes alongside dynamic changes in geometry, spin state, and electronic structure. This thesis investigates how intramolecular hydrogen bonding and ligand-centered redox activity can be strategically employed to modulate the structural and thermochemical behavior of copper and nickel complexes, offering insights into how molecular design principles can influence reactivity and electronic flexibility. </p><p dir="ltr">Across a series of structurally diverse Cu(II), Ni(II), and Pd(II) complexes supported by bidentate ureanylfunctionalized ligands, the role of secondary and tertiary coordination sphere effects in controlling solid-state geometry is explored. Systematic variations in metal identity, ligand substituents, solvent, and counterion reveal how non-covalent interactions guide coordination geometry, with single-crystal X-ray diffraction and DFT providing a predictive framework for structural outcomes.</p>