5KID:
reference: Engineered Recognition of Tetravalent Zirconium and Thorium by Chelator-Protein Systems: Toward Flexible Radiotherapy and Imaging Platforms., Captain I, Deblonde GJ, Rupert PB, An DD, Illy MC, Rostan E, Ralston CY, Strong RK, Abergel RJ, Inorg Chem. 2016 Nov 21;55(22):11930-11936. Epub 2016 Nov 1. PMID: 27802058

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