Aprotic Synthesis and Structural Determination of the Nanosized Nonprotonated ν₃-Octahedral [Pt₆Ni₃₈(CO)₄₈]^6- Hexaanion Stabilized as a Cubic Solvated [NMe₄]⁺ Salt

The nonprotonated member, 1 (n = 6), of the previously established nanosized ν3-octahedral [H6-nPt6Ni38(CO)48]n- series (n = 3−6) has been isolated from an aprotic synthetic route and stabilized as the crystal-ordered cyclohexane/acetonitrile-solvated [NMe4]+ salt. A highly precise X-ray determination (cubic; Pa3̄; Z = 4 with 1 possessing −3 site symmetry) has allowed a comparative analysis of the nonprotonated pseudo-D3d structure of 1 with the monoprotonated structure of 2 (n = 5), which constitutes the only previously reported complete geometry of any member of this extraordinary Pt6-encapsulated ν3-octahedral Pt6Ni38 cluster series.