Thermochemical transformations of gadolinium chloride and tetraphenylporphyrin into coordination complexes with imidazole ligands

The electronic structure and thermochemical formation of complex from gadolinium chloride and meso -tetraphenylporphyrin in presence of imidazole molecules were calculated using the Minnesota functionals family, ωB97XD, B3LYP and PBE0 with the relativistic all-electron ahlrichs_x2c vs ahlrichs_def2 with ECP and SDDall basis sets. Enthalpies and Gibbs free energies of all possible formations of ClGdTPP coordinated with different numbers of imidazole ligands (up to 2) and side products were compared. The coordination compound ClGdTPP·2Im was found as the most energetically preferable complex of the discussed reaction in molten imidazole medium at high temperature. Electronic structures and high multiplicities of intermediate gadolinium compounds and final coordination complexes were considered in details.