Lead iodide (PbI2) clusters were synthesized from the chemical reaction of NaI (or KI) with Pb(NO3)2 in H2O, D2O, CH3OH, and C3H7OH solvents. The observation of absorption features between the 550 and 350 nm region obtained with an integrating sphere strongly suggests PbI2 quantum dot formation in solution. Comparison of spectra of PbI2 clusters in solution with PbI2 clusters formed by impregnation of PbI2 in four different pore-sized porous silica substrates indicates that the PbI2 cluster size in solution is less than 2.5 nm in the lateral dimension. Atomic force microscopy (AFM) measurements of PbI2 solutions deposited on mica and highly oriented pyrolytic graphite surfaces indicate that the clusters are single layered. The measured height is 1.0 ± 0.1 nm, which is ∼0.3 nm larger than the layer thickness observed for the bulk materials. The swollen layer thickness can be attributed to the intralayer contraction from the strong lateral interaction among PbI2 molecules, which is supported by ab initio ca...

Chemical and Size Characterization of Layered Lead Iodide Quantum Dots via Optical Spectroscopy and Atomic Force Microscopy

Ab initio study of small zinc sulfide crystallites

Deposition of lead iodide films on Rh( 1 0 0 ) electrodes from colloidal solutions--the effect of an iodine adlayer

Effective Work Functions of the Elements

The electronic structure of cadmium chalcogenide clusters is calculated within the molecular orbital framework using the extended Huckel technique with charge self-consistency. The size of clusters calculated corresponds to one to three elementary cells (the largest cluster is Cd54S63). The results of the calculation show the tendency towards semiconductor-like band-structure formation. Explicit bands in the energy spectrum appear for clusters containing more than 100 atoms. There is good correspondence to experimental features of clusters in the optical and X-ray photoelectron spectra. The relative stability of clusters with different geometries and sizes is evidence of possible structure transformations in the case of small clusters. Most stable structures of small clusters are distinct from the bulk.

https://iopscience.iop.org/article/10.1088/0953-8984/6/42/002/pdf

Semiempirical calculation of cadmium chalcogenide clusters

Des amas lamellaires anisotropes du type Pb x I 2x sont etudies par des calculs ab initio de Hartree-Fock qui incluent les effets relativistes. On calcule les energies totales, les distances internucleaires et les charges atomiques nettes

M.M. Marino

Papers

Ab initio study of the geometry and electronic structure of lead iodide semiconductor clusters.

Ab initio study of the layered semiconductor cluster Bi6I18

Ab initio rep-based relativistic core/valence polarization operator

Ab initio study of the effects of cesium, hydrogen and oxygen adsorption on the work function of beryllium