Temperature and intensity ratios of the trans
For the cis conformer, a majority of the assignments between the previous study  and this present study have changed but for convenience the comparisons will be limited to vibrational modes in the finger print region below 1000 cm−1. The C–Cl stretch (υ8) was previously observed at 594 cm−1 where in the present study is observed at 536 cm−1. The COCl deformation (υ9) was originally observed at 444 cm−1 whereas in this investigation it (S)-Crizotinib was observed at 436 cm−1. The COCl rock (υ10) was originally predicted at 548 cm−1 and observed at 550 cm−1 but currently is predicted at 222 cm−1 but no peak was observed. The COCl wag (υ14) was previously predicted at 429 cm−1 and observed at 358 cm−1 and in present is predicted at 510 cm−1 and observed at 488 cm−1. The IR spectra of the solid observed at 489 cm−1 confirms both the prediction and assignment of the COCl wag. As with the trans conformer, the differences between the vibrational assignment of the previous study and this investigation include the potential energy distribution (P.E.D.) values and some modes have been switched between the two symmetric (A′) and antisymmetric (A″) blocks. Additionally we have reported vibrational assignment for the gauche conformer where the previous study  of fluoroacetyl chloride had not previously reported one.