S1 Synthesis and characterization of Cu-Ni mixed metal paddlewheels occurring in the metal-organic framework DUT-8(Ni0.98Cu0.02) for monitoring open-closed-pore phase transitions by X-band continuous wave EPR spectroscopy Supporting Information Matthias Mendt a,* , Sebastian Ehrling b , Irena Senkovska b , Stefan Kaskel b , Andreas Pöppl a a Felix Bloch Institute for Solid State Physics, Leipzig University, Linnéstr. 5, 04103 Leipzig, Germany b Department of Inorganic Chemistry, Dresden University of Technology, Bergstr. 66, 01062 Dresden, Germany * Email of corresponding author: matthias.mendt@uni-leipzig.de