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Mid-infrared transmission and absorption in polycrystalline chemical vapor deposition (CVD) diamond films has been studied. Free-standing films were grown in a DC arc-discharge plasma torch apparatus. The intensity of a band near 3.5 micron which was assigned in previous work to a C-H bond-stretching mode, correlates with the hydrogen concentration. One symmetric and one antisymmetric stretching mode were observed, with frequencies corresponding to an sp3-bonded CH2 species. In some films, the hydrogen-related absorption was reduced below 1 cm-1. A broadband at 8 micron scales in intensity with the 3.5-micron band, suggesting its association with hydrogen as well. A sharp feature at 1.330 to 1,335 cm-1 tentatively is assigned to defect-activated absorption by O(Gamma) phonons.