Ball and stick 3D model of the tetrakis(triphenylphosphine)palladium(0) molecule or tetrakis(triphenylphosphine)platinum(0) molecule. Atoms are color coded (carbon - black, phosphorus - red, palladium or platiunum - green, hydrogen - white). Pd i used as a catalyst for palladium-catalyzed coupling reactions. Applications include the Heck reaction, Suzuki coupling, Stille coupling, Sonogashira coupling, and Negishi coupling.