text: * Chromium carbonyl
  * Ferrocyanide
  * Iron pentacarbonyl
  * Nickel carbonyl
  * Tetrakis(triphenylphosphine)palladium(0)
  * Ferrocene
  * Uranium hexafluoride
  * tetraethyl lead
  * tetramethyl lead
  * tetrabutyl tin
  * trimethylaluminium
  * dimethylmercury
  * Diethylzinc
  * triethylborane
  * Chromate 
  * Permanganate 
  * Ferroin
  * bis(terpyridine)iron(II)