6BIH:
reference: The structure of the actin-smooth muscle myosin motor domain complex in the rigor state., Banerjee C, Hu Z, Huang Z, Warrington JA, Taylor DW, Trybus KM, Lowey S, Taylor KA, J Struct Biol. 2017 Dec;200(3):325-333. doi: 10.1016/j.jsb.2017.10.003. Epub 2017, Oct 14. PMID: 29038012

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