[Cu32(H)20{S2P(OiPr)2}12]: The Largest Number of Hydrides Recorded in a Molecular Nanocluster by Neutron Diffraction

An air‐ and moisture‐stable nanoscale polyhydrido copper cluster [Cu32(H)20{S2P(OiPr)2}12] (1H) was synthesized and structurally characterized. The molecular structure of 1H exhibits a hexacapped pseudo‐rhombohedral core of 14 Cu atoms sandwiched between two nestlike triangular cupola fragments of (2×9) Cu atoms in an elongated triangular gyrobicupola polyhedron. The discrete Cu32 cluster is stabilized by 12 dithiophosphate ligands and a record number of 20 hydride ligands, which were found by high‐resolution neutron diffraction to exhibit tri‐, tetra‐, and pentacoordinated hydrides in capping and interstitial modes. This result was further supported by a density functional theory investigation on the simplified model [Cu32(H)20(S2PH2)12]. Hydride sponge: A record number of 20 hydrides was revealed in an air‐ and moisture‐stable nanoscale copper cluster [Cu32(H)20{S2P(OiPr)2}12]. The presence of tri‐, tetra‐, and pentacoordinated hydrides within the peanut‐shaped copper framework was established by single‐crystal neutron diffraction and reproduced by DFT calculations. Addition of excess NaBH4 to the cluster produced unique rhombus‐shaped Cu nanoparticles (CuNPs, see figure).