Comparison of chemical properties of iron, cobalt, and nickel porphyrins, corrins, and hydrocorphins
Density functional calculations have been used to compare the geometric, electronic, and functional properties of the three important tetrapyrrole systems in biology, heme, coenzyme B12, and coenzyme F430, formed from iron porphyrin (Por), cobalt corrin (Cor), and nickel hydrocorphin (Hcor). The results show that the flexibility of the ring systems follows the trend Hcor > Cor > Por and that the s
