Self-assembling iron and manganese metal-germanium-selenide frameworks:: [NMe4]2MGe4Se10, where M = Fe or Mn

The hydtothermal synthesis mixture GeSe-(TMA)OH-H2O (TMA(+) = NMe4+) yielded crystals of the material (TMA)(2)Ge4Se10. A single-crystal X-ray diffraction structure showed the presence of adamantanoid Ge4Se104- clusters and TMA(+) cations. The TMA(+) template-mediated aqueous synthesis of (TMA)(2)MGe4Se10 (M = Mn or Fe) from Ge4Se104- and M2+ building-blocks is described. Rietveld powder X-ray diffraction full profile structure refinements of (TMA)(2)MGe4Se10 established that these novel metal-germanium-selenide frameworks are isostructural with the analogous metal-germanium-sulfides, (TMA)(2)MGe4S10. The selenide materials have a zinc blende-type of open-framework structure. Charge-balance of the anionic open-framework [MGe4Se10](2-) is maintained by two TMA(+) template cations that reside within the cavity spaces Trends in the tetragonal unit cell dimensions and metal-chalcogenide bond lengths of (TMA)(2)MGe4X10 (X = S or Se) are those expected based upon increases in metal and chalcogenide radii on passing from S-II to Se-II and Fe-II to Mn-II.