[kphiller]

In a recent Advanced Higher investigation I have been comparing the paramagnetic effects of transition metal complexes in solid and aqueous states. My results showed that both Copper (II) Sulphate Pentahydrate and Manganese (II) Sulphate (MnSO4.H2O) exerted a greater paramagnetic force per mole when aqueous than when solid. Unfortunately I have been unable to explain why this is. I had initially thought that upon forming a metal aquo complex the degree of d-orbital splitting (the energy gap between the lower three d-orbitals and the upper d-orbitals) had been reduced changing each of the complexes from low spin to high spin, therefore meaning there is a greater number of unpaired electrons and a greater paramagnetic force exerted per mole. However, each of the two complexes are already high-spin when solid meaning this reasoning does not make sense. I would like to know if a reason exists that can explain these results or if my results are just inaccurate and cannot be explained. Any help would be appreciated. Thanks