Inorganic chemistry
Inorganic chemistry is the branch of chemistry which is concerned with the properties and behavior of the inorganic compounds. This field covers all the chemical compounds except the myriad organic compounds (carbon based compounds, containing C-H bonds).
Coordination compounds: Classical coordination compounds feature metals bound to "lone pairs" of electrons residing on main group atoms of ligands like NH3, H2O, Cl−, and CN−. In modern coordination compounds almost all the organic and inorganic compounds can be used as ligands. The "metal" commonly is a metal from the groups 3-13, as well as the trans-lanthanides and trans-actinides, but from a certain perspective, all the chemical compounds can be described as coordination complexes.
Main group compounds: These species feature elements from the groups 1, 2 and 13-18 (expect hydrogen) of the periodic table. Due to their often similar reactivity, the elements in group 3 (Sc, Y, and La) and group 12 (Zn, Cd, and Hg) are also included generally.
Transition metal compounds: Compounds having metals from group 4 to 11 are considered transition metal compounds. Compounds with a metal from the group 3 or 12 are at times also incorporated into this group, but also often classified as main group compounds.
Organometallic chemistry: Usually, organometallic compounds are to contain the M-C-H group. The metal (M) in these species can be a main group element or a transition metal. Organometallic compounds are mainly considered a special category because organic ligands are not sensitive to hydrolysis or oxidation, necessitating that the organometallic chemistry employs more specialized preparative methods than was traditional in the Werner-type complexes.
Cluster compound: Clusters can be found in all the classes of chemical compounds. According to the widely accepted definition, a cluster consists minimally of a triangular set of atoms that are directly bonded to each other. But metal-metal bonded dimetallic complexes are quite relevant to the area. Clusters occur in "pure" inorganic systems, organometallic chemistry, bioinorganic chemistry and main group chemistry.