Stability and kinetics of the acid-promoted decomposition of Cu(ii) complexes with hexaazacyclophanes: kinetic studies as a probe to detect changes in the coordination mode of the macrocyclesElectronic supplementary information (ESI) available: Table S1: Observed rate constants for the decomposition of the different Cu(ii) complexes with ligands L1?L6. Fig. S1: Spectral changes recorded during the decomposition of the H2CuL4+ (a) and HCuL3+ (b) complexes of L2 in the presence of 0.01 M HNO3. See http://www.rsc.org/suppdata/dt/b3/b311772c/