VIBRATIONAL PROPERTIES OF SILOXENE - ISOTOPE SUBSTITUTION STUDIES

The vibrational properties (IR and Raman) of the two-dimensional sheet polymer siloxene (Si6O3H6) are studied using H-1-H-2 and O-16-O-18 su bstitution. While the stretching vibrations shift as expected under th e substitution experiments, the low frequency bending vibrations shift anomalously. in particular, the lines previously attributed to a sili con phonon mode (514 cm(-1) in IR and 496 cm(-1) in Raman) show the ty pical H-D isotope shift in IR, but appear to harden to 575 cm(-1) in R aman scattering. These results contain important information about the siloxene microstructure. (C) 1998 Elsevier Science B.V. All rights re served.