(1943–2012), Mexican chemist. His work with F. Sherwood Rowland (1927–2012) on the behaviour of CFCs used as propellants led to his discovery that these collect in the upper atmosphere where they are broken down by ultraviolet light, releasing free chlorine atoms that are damaging to ozone. Nobel Prize for Chemistry (1995, with Rowland and Paul Crutzen (b.1933)).