Organometallic radiation resist compositions are described based on tin ions with alkyl ligands. Some of the compositions have branched alkyl ligands to provide for improved patterning contrast while maintaining a high degree of solution stability. Blends of compounds with distinct alkyl ligands can provide further improvement in the patterning. High resolution patterning with a half-pitch of no more than 25 nm can be achieved with a line width roughness of no more than about 4.5 nm. Synthesis techniques have been developed that allow for the formation of alkyl tin oxide hydroxide compositions with very low metal contamination.