Crystal field theory
Crystal Field Theory (CFT) is a scientific representation of how metals behave when dissolved in water to form a special type of chemical called a complex. This model may be used to predict the colors of certain metal containing chemicals when dissolved in water, as well as their reactions when placed near a magnet. It may also be use to predict the shape of the chemicals. CFT  does not predict the connections between atoms. CFT  was created by physicists Hans Bethe and John Hasbrouck van Vleck in 1930. It was later combined with the molecular orbital theory to create the ligand field theory, which does describe the connections between atoms.