Switched to {{Infobox model parameter}} and fixed the units.
{{Infobox model parameter| name = {{PAGENAME}}| param = <onlyinclude>''Δω''<sup>2</sup><noinclude/onlyinclude> Chemical | desc = The chemical shift difference between sites A and B , squared, in (2-site).| equation = ({{:omegaB}} - {{:omegaA}})<sup>2</sup>| units = rad<sup>2</sup>.s<sup>-12</sup>.}}