RAMAN MICRO-PROBE SPECTRA AND VIBRATIONAL-MODE ASSIGNMENTS OF TALC

The Raman spectra of talc microparticles have been obtained with the Raman microrpobe over the frequency range 100 to 3800 cm** minus **1. The vibrational modes are discussed in terms of an idealized unit cell (1-M polymorph) of C//2//h symmetry. An electrostatic dipole-dipole interaction is used to compare the Raman and infrared active branches. Assignments of the Raman active stretching modes of the silicate sheet are found to support previous infrared assignments. Estimates of intrasheet dipole-dipole interactions are obtained.