Inorganic−Organic Hybrid Composites Containing MQ (II−VI) Slabs: A New Class of Nanostructures with Strong Quantum Confinement and Periodic Arrangement

A new class of nanostructures has been prepared and characterized. These nanocomposite hybrid materials are composed of two-dimensional MQ (II−VI) slabs and organic bifunctional molecules that act as links as well as spacers. The most intriguing properties of these nanostructures are that they exhibit strong quantum confinement effect while possessing a perfectly periodic arrangement. The crystal structures of [MnSe(en) 0.5 ] ( 1; en = ethylenediamine), [MnSe(pda) 0.5 ] ( 2; pda = propanediamine), [ZnSe(en) 0.5 ] ( 3 ), and [ZnSe(pda) 0.5 ] ( 4 ) have been analyzed by single crystal and powder X-ray diffraction methods. Compounds 1 and 3 are isostructural and crystallize in orthorhombic crystal system, space group Pbca (No. 61), Z = 4. Crystal data for 1: a = 6.711(1), b = 6.614(1), c = 17.720(4) Å, For 3: a = 6.6326(7), b = 6.4630(6), c = 17.3540(16) Å. Compounds 2 and 4 are isostructural and crystallize in orthorhombic crystal system, space group Cmc 2 1 (No. 36), Z = 4. Crystal data for 2: a = 20.384(4), b = 6.719(1), c = 6.565(1) Å. For 4: a = 19.9731(18), b = 6.6268(7), c = 6.4394(6) Å. The optical absorption experiments show that both 3 and 4 generate a very large blue shift in the absorption edge (1.4−1.5 eV), and both compounds are thermally stable up to 250 °C.