Spontaneous formation of autocatalytic sets with self-replicating inorganic metal oxide clusters

Here we show how a simple inorganic salt can spontaneously form autocatalytic sets of replicating inorganic molecules that work via molecular recognition based on the {PMo(12)} ≡ [PMo(12)O(40)](3–) Keggin ion, and {Mo(36)} ≡ [H(3)Mo(57)M(6)(NO)(6)O(183)(H(2)O)(18)](22–) cluster. These small clusters are able to catalyze their own formation via an autocatalytic network, which subsequently template the assembly of gigantic molybdenum-blue wheel {Mo(154)} ≡ [Mo(154)O(462)H(14)(H(2)O)(70)](14–), {Mo(132)} ≡ [Mo(VI)(72)Mo(V)(60)O(372)(CH(3)COO)(30)(H(2)O)(72)](42–) ball-shaped species containing 154 and 132 molybdenum atoms, and a {PMo(12)}⊂{Mo(124)Ce(4)} ≡ [H(16)Mo(VI)(100)Mo(V)(24)Ce(4)O(376)(H(2)O)(56) (PMo(VI)(10)Mo(V)(2)O(40))(C(6)H(12)N(2)O(4)S(2))(4)](5–) nanostructure. Kinetic investigations revealed key traits of autocatalytic systems including molecular recognition and kinetic saturation. A stochastic model confirms the presence of an autocatalytic network involving molecular recognition and assembly processes, where the larger clusters are the only products stabilized by the cycle, isolated due to a critical transition in the network.