Excitonic bands in the photoconductivity spectra of some organic-inorganic hybrid compounds based on metal halide units

The photoconductivity (PC) spectra of the compounds CH3NH3PbI3, [CH3NH3][CH3C6H4 CH2NH3]2Pb2I7, [CH3C6H 4CH2NH3]2PbI4, [H2NC(I)=NH2]3PbI5 as well as the spectra of similar compounds based on C10H21SC(NH2)2, H3N(CH2)6NH3, C14H9CH2SC(NH2)2, SnI4, PbClxI4-x, and PbBrxI4-x are described. The position, intensity and shape of the PC bands depend on the dimensionality (or size) of the inorganic network as well as on the nature of metal halide and the organic groups. Excitonic features are discussed

Optical and related properties of natural one-dimensional semiconductors based on PbI and SnI units

Optical absorption, reflectance, photoluminescence, photoluminescence excitation and photoconductivity spectra of [NH2C(I)=NH2]3MI5 (M=Pb, Sn), (Bu4N)PbI3 and similar 1D semiconductors at room temperature are reported and compared with those of the corresponding 2D and 0D analogues

Some unsymmetrical nickel 1,2-dithiolene complexes as candidate materials for optics and electronics

The unsymmetrical complexes Ni(tmedt)(dddt), Ni(dpedt)(dddt), Ni(tmedt)(dmit), and Ni(dpedt)(dmio) (where tmedt is trimethylene-ethylenedithiolate, dddt is 5,6-dihydro-1,4-dithin-2,3-dithiolate, dmit is 1,3-dithiol-2-thione-4,5-dithiolate, dpedt is diphenyl-ethylenedithiolate, and dmio is 1,3-dithiol-2-one-4,5-dithiolate) were prepared and their structural and physical properties investigated. The results were compared with those obtained from similar unsymmetrical and the corresponding symmetrical complexes. The new complexes were found to be stable in air and exhibit the necessary structural and physical properties in order to be candidate materials for optical and electronic devices. © 2008 Elsevier Masson SAS. All rights reserved