NHNOOOHCOOHNHNOOOHCOOHOOOHCOOHNONNEuNNOHOHOHNHNOOO-CO2--OO-CO2-NONHNOOO-CO2-OEu(Phen)23+Eu(Phen)23+Eu(Phen)23+123--Eu-1Eu-2Eu-311115118118115