Multi-physics predictive framework for thermolysis of titanium(IV)-isopropoxide

Leveraging high reactivity and volatility of metal-organic (MO) precursors, hybrid molecular beam epitaxy enables precise synthesis of complex oxides with tailored properties. However, the MO thermal decomposition and surface reaction mechanisms are highly complex and not yet fully understood. For instance, thermolysis of the widely employed titanium(IV)-isopropoxide (TTIP) is generally assumed to take place by C-O bond dissociation via β-hydride elimination process. Here, we report the comprehensive analysis of the complete kinetic scheme for TTIP decomposition based on a hybrid computational framework of quantum mechanics, ReaxFF molecular dynamics and metadynamics simulations, challenging the oversimplified and conventionally assumed scenario. Our combined approach showed that the initial organic ligand separation step was spontaneous and occurred predominantly via C-O bond dissociation, albeit not always via β-hydride elimination. Additional reaction pathways involved Ti-O bond dissociation. This novel MO chemistry evaluation strategy constitutes a predictive and cost-effective framework for engineering novel precursors, laying a foundation for the computational design of untapped MO precursors with tailored decomposition pathways, thus affording rapid and cost-effective advancements for existing and future applications of chemical vapor deposition based thin film growth and coating processes.