Infra-red spectra were collected using a Thermo Scientific spectrometer model NICOLET iS5 using 64 scans and a resolution of 4 cm -1 . 1 H-NMR spectra were measured with a Bruker AVANCE 400 NMR spectrometer at 25 °C operating at 400.13 MHz for 1 H. For acid digestion of the complexes, ca. 15 mg of the complex were suspended in DMSO-d6 and 40 μL of DCl solution was added. The mixture was left to stand 3 h at RT, resulting in a yellow solution suitable for NMR measurements. Thermogravimetric analyses (TGA) were performed with a NETZSCH STA 449 F1 Jupiter under N2 using an isotherm for 10 min at 30°C before heating up to 500 °C at a rate of 10°Cmin -1 . Powder X-ray diffraction (PXRD) data were collected in a flat plate configuration using a Bruker D8 Discover diffractometer equipped with Cu Kα source (λ = 1.54056 Å). SEM samples were prepared by placing a small amount of sample on a conductive carbon adhesive label attached to a metal tack, which was sputter coated using a palladium disc connected to a Polar SC500A coater. Coating was carried out for four minutes at a current density of 20 mA under an argon atmosphere. SEM images were taking on a JEOL JSM-IT100 with a Tungsten source and operating at 5 kV and 40 mA current. For gas sorption measurements, all samples were activated in situ by heating at 413 K for 10 hours under vacuum before measuring their N2 uptake at 77 K using a Micrometrics ASAP 2420 (University of Strathclyde) and CO2 (195 K) using a BELSORP-miniX volumetric adsorption instrument from BEL Japan, Inc (iCeMS, Kyoto University).