Complexes and First-Row Transition Elements

Abstract

The chemistry of the transition elements is very largely concerned with the chemistry of co-ordination compounds. Co-ordination compounds or, as they are perhaps more usually called, complexes play a very important part in our lives today; the study of them has contributed greatly to our understanding of the chemical bond and of inorganic chemistry as a whole. The number of possible co-ordination compounds in chemistry is almost infinite. Present-day research workers prepare many new complexes every week; most of these will be of academic interest only, but just a few will be of considerable economic importance as well. For many years complexes were regarded as of interest to the theoretical and inorganic chemist only, but now they are playing vital roles in analytical chemistry, in the synthesis of organic chemicals, in polymerisation processes, and in our understanding of biological processes. Perhaps the most important are the naturally occurring complexes such as chlorophyll, the magnesium complex that is important in plant photosynthesis, and haemoglobin, the iron complex that is a carrier of oxygen in blood.