Electronic Structure of Nitrogen Square Planar Copper Complexes in Langmuir-Blodgett Films

S. Carniato (1) , Henri Roulet (1) , Georges Dufour (1) , Serge Palacin (2) , André Barraud (2) , Philippe Millié (3) , Irène Nenner (3)

1 LCPMR - Laboratoire de Chimie Physique - Matière et Rayonnement
2 SCM - Service de Chimie Moléculaire
3 SPER - Service de Photochimie et Etude de la Réactivité

We show by X-ray induced photoelectron spectroscopy (XPS) that the amphiphilic tetrapyridinoporphyrazinium CuS18 undergoes different redox modifications when in the amorphous phase or in LB films. In the case of the LB films, CuS18 appears in a two-electron reduced state, but the XPS spectrum is surprisingly dominated by a copper(II) signal. On the contrary, amorphous CuS18 is spontaneously reduced on the copper atom when exposed to various X-ray irradiations. Semi-empirical calculations show that the extra electrons can be added either on the macrocycle (LB films) or on the metallic ion (amorphous phase), probably depending on a slight geometric distortion around the cupric ion within the LB films.

Domaines: Matériaux

S. Carniato, Henri Roulet, Georges Dufour, Serge Palacin, André Barraud, et al.. Electronic Structure of Nitrogen Square Planar Copper Complexes in Langmuir-Blodgett Films. Thin Solid Films, 1992, 210-211, pp.519-520. ⟨10.1016/0040-6090(92)90329-A⟩. ⟨cea-01057151⟩