Vibrational and optical properties of a one‐dimensional organic–inorganic crystal [C 6 H 14 N]PbI 3

Self‐assembled organic–inorganic [C 6 H 14 N]PbI 3 crystals were synthesized. The crystal structure consists of one‐dimensional semiconductor chains formed by infinite PbI 6 face‐sharing octahedra aligned along the a ‐axis. The organic cations are linked to the inorganic chains by NH· · ·I hydrogen bonds and act as insulator barriers. The vibrational properties of [C 6 H 14 N]PbI 3 were studied using polarized Raman scattering and infrared (IR) absorption. The observed Raman and IR spectral features were identified by comparison with the vibrational properties of homologous compounds and with the vibrational wavenumbers calculated using the ab initio PM3 method. Moreover, the photoluminescence and diffuse reflectance of [C 6 H 14 N]PbI 3 single crystals, along with the UV‐Vis absorption of spin‐ coated films, were measured. A strong green‐blue luminescence due to radiative recombinations of 1D excitons is observed. The Stokes shift is estimated at 70 meV. Copyright © 2008 John Wiley & Sons, Ltd.