The behaviour of the KMPS ₄ (M=Ni, Pd) salts and some solid-solution phases, KNi _x Pd _1–x PS ₄ , when dissolved in dimethylformamide (DMF) have been studied. For KNiPS ₄ -DMF the novel re-arranged molecular bowl-like [Ni ₃ P ₃ S ₁₂ ] ^3– trianion can be formed from solutions that have been heated at 323 K for 2 days and K ⁺ exchanged by larger organic cations such as PPh ₄ ⁺ (tetraphenylphosphonium), TMA ⁺ (tetramethylammonium), TEA ⁺ (tetraethylammonium), and MEM ⁺ (methylethylmorpholinium). This remarkable dispersion/auto-fragmentation/re-arrangement sequence extends the concept of mere excision in solution of monomeric molecular motifs from low-dimensional inorganic solids. Investigations by electrospray mass spectrometry (ESMS), ³¹ P solution-state NMR and optical microscopy under polarized light of KNiPS ₄ in DMF have shown that chains of[MPS ₄ ] ^– exist intact in freshly prepared solutions. These solutions show transient birefringence under stress. ESMS and NMR studies of KNiPS ₄ solutions show that the [NiPS ₄ ] ^– chains are quickly broken down at ambient temperature and that cyclic [Ni ₃ P ₃ S ₁₂ ] ^3– trianions are formed. By contrast, the [PdPS ₄ ] ^– chain remains intact at temperatures up to 323 K. This behavioural difference can be understood in terms of the Ni-S and Pd-S bond strengths. ESMS spectra of aged KNi _x Pd _1–x PS ₄ /DMF solutions indicate that mixed metal trianions are formed, such as [Ni ₂ PdS ₁₂ ] ^3– , [NiPd ₂ P ₃ S ₁₂ ] ^3– and [Ni ₃ P ₃ S ₁₂ ] ^3– , but no [Pd ₃ P ₃ S ₁₂ ] ^3– species have yet been observed.