5NQN:
reference: Visualizing Biological Copper Storage: The Importance of Thiolate-Coordinated Tetranuclear Clusters., Basle A, Platsaki S, Dennison C, Angew Chem Int Ed Engl. 2017 Jul 17;56(30):8697-8700. doi:, 10.1002/anie.201703107. Epub 2017 Jun 19. PMID: 28504850

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).