Vibrational Intensities in Halogenated Methanes. I. Methylene Chloride

The absolute infrared absorption intensities of four fundamental bands in CH2Cl2 have been measured in the vapor state. The intensities that have been observed are A6 (CH stretching)=48.0×1010 cycles/sec at NTPA7 (CH rocking)=13.0×100 cycles/sec at NTPA8 (CCl stretching)=1420.0×1010 cycles/sec at NTPA9 (CCl rocking)=375.0×1010 cycles/sec at NTP.These data indicate that the bond moments and bond derivatives are μCH=+0.45×10−18 esuμCCl=−0.95×10−18esu∂μCH/∂rCH=+0.3×10−10 esu or −0.2×10−10 esu∂μCCl/∂rCCl=+3.7×10−10 esu.It was not possible to resolve the ambiguity in signs that lead to the alternate values of ∂μCH/∂rCH.