Depending on the stoichiometric ratio, squaric acid (H(2)SQA) reacts with [Co(eta(5)-C5H5)(2)][OH] to form crystalline materials based on anion-cation pi-pi stacks and/or squarate ion ribbons held together by O-H ... O hydrogen bonds between squarate anions and by charge-assisted C-Hdelta+... Odelta- hydrogen bonds between organometallic and organic components.