Conformations and Coordination Types of Glutarate Ions in Complexes f-Metals

A crystal chemical analysis of all known f-metal compounds containing glutarate ions C5H6O $$_{4}^{{2 - }}$$ was carried out. It was established that 154 crystallographically nonequivalent glutarate ions exhibit 11 topologically different types of coordination to f-metal atoms in the crystal structures. It was found that for aliphatic dicarboxylate ions [O2C–(CH2)n–CO2]2– at n > 1 are characterized by types of coordination that lead to the formation of four-membered metallocycles. Using glutarate ions as an example, a new method for quantitatively assessing the conformation of chains consisting of five carbon atoms linked by single bonds has been tested for the first time. C–C bonds. It is shown that in the characterized structures, 154 glutarate ions realize four different conformations, each of which corresponds to a certain “double” symbol: φ3/φ3, φ1/φ3, φ1/φ1, or φ1/φ2.