In-plane and out-of-plane optical properties of NdBa2Cu3Ox single crystalsclose to x=7.0

We present results of reflectivity measurements with E parallel to c and E perpendicular to c on NdBa2Cu3Ox (Nd123) single crystals close to full oxyg en doping. Along the c-axis the optical conductivity sigma(1)(c) shows a we ll developed absorption band around 450 cm(-1) at, all temperatures. The in -plane optical properties are dominated by crystal-field excitations at lou r energies, a prominent step at 400 cm(-1) and a weaker feature between 500 - 550 cm(-1). A comparison of sigma(1)(c) and the in-plane scattering rate Gamma(ab)(omega) with neutron scattering derived spin susceptibility spect ra suggests that the in-plane and out-of-plane anomalies are caused by the same mechanism, probably electron-spin scattering.