Synthesis and Biological Activity of Alkline Earth Metal Complexes

In order to explain the formulae and structures of the complex compounds or complexes, formed by transition metal salts with molecular species such as ammonia, Werner coined the terms primary valence and secondary valence.. These concepts remain valid today except that the term oxidation state has replaced ¿primary valence¿ and the term coordination number has replaced ¿secondary valence¿ Werner had recognized that a transition metal salt could form a complex compound in which the metal ion became bonded to a number of groups which need not necessarily be the counter anions originally present in the salt. The orientations in space of these metal-bond groups would lead to the complex having a particular geometric structure. Coordination compound has always been a challenge to the inorganic chemistry. The scientists of coordination of compound are Kooser , Lewis, Sidgwick, etc.