Neutral Octa‐Adamantane Chalcogenidometalate Clusters via Amine Complexation and Organotin Termination for Nanolithography

Abstract

Abstract Supertetrahedral chalcogenidometalate clusters, inspired by zinc‐blende‐type quantum dots, integrate both chemical and geometrical uniqueness. However, their inherent negative charge and rigid T d symmetry restrict configurational diversity and functional utility. Herein, a synergistic strategy combining polyamine coordination and butyltin termination is employed to synthesize neutral chalcogenidometalate supertetrahedral clusters. Two distinct classes are presented: (1) tetra‐adamantane clusters (TA‐amine; amine = tris(2‐aminoethyl)amine (TAEA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA)) with 14 metal sites and (2) octa‐adamantane clusters (OA‐X; X═S/Se) with 20 metal sites—the largest neutral supertetrahedral clusters known to date. The OA‐X clusters exhibit unprecedented C 2v geometry, deviating from conventional T d , thereby validating the efficacy of polyamine‐arylstannane synergy in advancing cluster chemistry. Charge neutrality and peripheral organic shells confer exceptional solubility and stability in some common solvents, enabling the fabrication of high‐quality films for nanopatterning. Electron beam lithography (EBL) reveals that OA‐X‐based films enable 50 nm line patterning, with the OA‐Se version demonstrating the higher sensitivity—a result attributable to the large photoabsorption cross‐section of selenium. Solubility‐switching behavior is attributed to radiation‐induced phase transitions from discrete clusters to chalcogenidometalate nanoparticles. This work bridges molecular precision with functional material design, offering insights into charge‐neutral cluster engineering for extreme ultraviolet (EUV) nanolithography.