Investigations on bismuth oxido clusters are focused on the nucleation and growth processes towards large cluster motifs and their stability in the gas phase, which has been studied by electrospray ionization mass spectrometry (ESI-MS), molecular dynamics (MD) simulations and X-ray scattering experiments evaluated by pair distribution function (PDF) analysis. The formation of metastable bismuth(III) oxides was obtained by hydrolysis of polynuclear bismuth oxido clusters and subsequent thermal treatment under non-equilibrium conditions. Temperature dependent PXRD and Raman spectroscopic experiments gave insight into the formation process of metastable β-Bi₂O₃ starting from the amorphous hydrolysis products as-obtained from polynuclear bismuth oxido clusters. Furthermore, PXRD as well as energy-dispersive X-ray (EDX) spectroscopy confirmed the formation of several new ternary bismuth(III) rich oxides such as Bi₁₄O₂₀(MO₄) (M = S, Se) as-obtained by hydrolysis of bismuth oxido clusters in the presence of diverse additives.