Normal Coordinate Treatment for the Out-of-Plane Vibrations of Ethylene-Type Molecules

The s vectors for torsional and out-of-plane bending modes of vibration for ethylene-type molecules are given. Then F- and G-matrix elements are given for all ethylene-type molecules with the exception of C2XYZW isomers. Finally, numerical calculations are carried out for C2H4, asymmetric C2H2F2, asymmetric C2H2Br2, the cis- and trans-isomers of C2H2Cl2 and all of their deuterated analogs. The 57 out-of-plane fundamentals were calculated for the above 19 molecules. Of these 57 fundamentals 50 have been reported in the literature and are reproduced in this paper with an average deviation of 2.2 K or to 0.362% error.