Temperature dependences of the magnetic susceptibility and heat capacity C p of CdSe quantum dots with size d = 2.8, 4.1, and 5.6 nm are compared to those of bulk CdSe to determine the size-dependent effects. With decreasing size d, the following effects are observed: ͑i͒ room temperature optical absorption shows a blueshift of the band gap; ͑ii͒ room temperature x-ray diffraction show wurtzite structure but with smaller lattice constants; ͑iii͒ magnetic susceptibility changes from negative ͑diamagnetic͒ for the bulk to positive with magnitude increasing with decreasing d; and ͑iv͒ the Sommerfeld constant ␥ determined from the C p / T vs T 2 data increases. Possible explanations for these size-dependent properties are presented.

The dicarboxylate anions 1,4-benzenedicarboxylate and fumarate can be selectively intercalated into the layered double hydroxide [LiAl 2 (OH) 6 ]Cl‚H 2 O from equimolar molar mixtures of the 1,2-, 1,3-, and 1,4-benzenedicarboxylate and fumarate and maleate isomers, respectively. Time-resolved in situ energy-dispersive X-ray diffraction studies have shown that these are the thermodynamic products following the conversion of an initial phase in which all the anions are simultaneously intercalated.

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