Wrighton, Mark S.
He is Chancellor Emeritus Mark S. Wrighton; Wrighton or the chancellor emeritus are OK on second reference. He is also a professor in the Department of Chemistry in Arts & Sciences, but only use this title if a story references research or an academic exercise in chemistry.
Wrighton’s wife is Risa (Ree-suh) Zwerling Wrighton. On second reference, her preference is Zwerling Wrighton (no hyphen).