Size-quantization

When electronic particles such as electrons and holes are constrained by potential barriers to regions of space that are comparable to or smaller than their de Broglie wavelength, the corresponding allowed energy states become discrete (i.e. quantized) rather than continuous. This manifests in the absorption (or emission) spectra as discrete lines that are reminiscent of atomic (line) transitions these sharper features often appear superimposed on a broader envelope. Another manifestation 

Size quantization effects and quantum dot photoelectrochemistry are discussed in more detail elsewhere in this volume. 

---

Yokoyama T and Takayanagi K 1999 Size quantization of surface state eiectrons on the Si(OOI) surface Phys. Rev. B 59 12 232... 

Henglein A 1988 Mechanism of reactions on colloidal microelectrodes and size quantization effects Top. Curr. Chem. 143 115... 

Mechanism of Reactions on Colloidal Microelectrodes and Size Quantization Effects... 

Lead(II) sulfide occurs widely as the black opaque mineral galena, which is the principal ore of lead. The bulk material has a band gap of 0.41 eV, and it is used as a Pb " ion-selective sensor and IR detector. PbS may become suitable for optoelectronic applications upon tailoring its band gap by alloying with II-VI compounds like ZnS or CdS. Importantly, PbS allows strong size-quantization effects due to a high dielectric constant and small effective mass of electrons and holes. It is considered that its band gap energy should be easily modulated from the bulk value to a few electron volts, solely by changing the material s dimensionality. 

Electrodeposition of Nanostructures Size-Quantized Films on Metal Substrates... 

Torimoto T, Nagakubo S, Nishizawa M, Yoneyama H (1998) Photoelectrochemical properties of size-quantized CdS thin films prepared by an electrochemical method. Langmuir 14 7077-7081... 

Torimoto T, Obayashi A, Kuwabata S, Yasuda H, Mori H, Yoneyama H (2000) Preparation of size-quantized ZnS thin films using electrochemical atomic layer epitaxy and their photoelectrochemical properties. Langmuir 16 5820-5824... 

Mastai Y, Hodes G (1997) Size quantization in electrodeposited CdTe nanocrystalline films. 

Baral S, Fojtik A, Weller H, Henglein A (1986) Photochemistry and radiation chemistry of coUoidal semiconductors. 12. Intermediates of the oxidation of extremely small particles of cadmium sulfide, zinc sulfide, and tricadmium diphosphide and size quantization effects (a pulse radiolysis study). J Am Chem Soc 108 375-378... 

---