(LaSe)(1.14)(NbSe2)(2) - a metal-insulator quantum well crystal?

We report on the polarized IR and Raman study of the misfit layer compound (LaSe)(1.14)(NbSe2)(2). The obtained data were compared with those obtained on the parent layer compounds LaSe and NbSe2. On an assumption of a charge transfer of 1.14 electrons per formula unit from the LaSe to the NbSe2 layers the decrease of the plasma frequency in the misfit compound with respect to that in the parent layer compounds is qualitatively explained. A qualitative model of electronic structure formation of the misfit layer compound from electronic bands of the parent layer compounds is discussed. An in-plane optical anisotropy related to the small misfit between the LaSe and NbSe2 layer structures has been detected.