POLARIZED CHARGE-TRANSFER SPECTRA OF CU2-XCL4 (X=0-1)( DOPED PEROVSKITE LAYERS (RNH(3))(2)CDXMN1)

This work investigates the charge transfer spectra of CuCl64- complexe s formed in the (RNH(3))(2)CdxMn1-xCl4 crystal series. For x = 1, it i s demonstrated that Cu complexes display an elongated D-4h symmetry, f orming an antiferrodistortive type structure which is similar to that found in the pure copper crystals. The presence of Mn induces an impor tant enhancement of the charge transfer bands as well as significant r edshifts. The results are interpreted in terms of distortions of the C uCl64- geometry which changes from D-4h elongated (x = 1) to nearly D- 4h compressed (x = 0). The transition energy, polarization and assignm ent of the charge transfer bands are analysed.