The NSD method, as developed by Shelnutt and coworkers, was used to delineate, quantify, and illustrate the various distortions modes present in the tetrapyrrole macrocycles. Analysis was performed with the NSD online interface, available at . Single crystal X-ray crystallography: Crystals were grown following the protocol developed by Hope, liquid-liquid diffusion of CHCl3 and MeOH with H2SO4. Diffraction data were collected on a Bruker APEX 2 DUO CCD diffractometer using Incoatec IμS Cu-Kα (λ = 1.54178 Å) radiation. Crystal was mounted on a MiTeGen MicroMount and collected at 100(2) K using an Oxford Cryosystems Cobra low-temperature device. Data were collected using omega and phi scans and were corrected for Lorentz and polarization effects using the APEX software suite. Data were corrected for absorption effects using the multi-scan method (SADABS). Using Olex2, the structure was solved with the XT structure solution program, using the intrinsic phasing solution method and refined against │F 2 │ with XL using least-squares minimization. If electron density was not sufficient, the C and N bound H atoms were placed in their expected calculated positions and refined using a riding model: N-H = 0.88 Å, C-H = 0.95-0.98 Å, with Uiso (H) = 1.5Ueq (C) for methyl H atoms and 1.2Ueq (C, N). Details of data refinements can be found in Table . All images were prepared using Olex2. In the structure α2β2-P[SO4 2-][HSO4 -]4, two phenyl rings at C5 and C10 and one ethyl group are modelled over two locations using DFIX, SIMU, SADI restrains and EADP constraints. In terms of counter anion, only the SO4 2-group is not disordered, while all other HSO4 -groups were modelled disordered using rigid groups. Some hydrogen atoms were placed geometrically to compensate for close contacts, the remaining hydrogens could not be located on the disordered HSO4 -moieties but were added to the formula to make the formula weight correct. Multiple disordered and partially occupied H2O molecules are modelled in the structure using SIMU and ISOR restrains. The weighting scheme was manually adjusted to ensure the goodness of fit was reasonable.