“…The data presented here are qualitatively similar to those presented in a previous article. 3 The bands can be assigned to the following absorption modes: Si-C stretching located at about 780 cm Ϫ1 , 9,22,23 rocking and/or wagging vibrations of CH n in Si-CH n at about 950 cm Ϫ1 , 22,24,25 stretch vibrations for Si-H at 2100 cm Ϫ1 and C-H at 2900 cm Ϫ1 . 22,9 Two additional peaks centered at 1250 and 1350 cm Ϫ1 , present only in hydrogen rich films, 9 can also be attributed to C-H bonds: the absorption bands from 1200 to 1500 cm Ϫ1 are due to bending and scissoring modes of CH 2 , CH 3 , Si͑CH 3 ͒, and C͑CH 3 ͒.…”