Table 4.
Selected harmonic MP2/aug-cc-pVDZ(-PP) vibrational frequencies, in cm−1, and infrared intensities, in km mol−1, for the halogen bonded complexes of benzene and CF3Cl, CF3Br and CF3I, respectively.
| Mode | νmonomer | IR intensity | νcomplex | IR intensity | Δν |
|---|---|---|---|---|---|
| CF3Cl | |||||
| ν1 | 1097.0 | 469.7 | 1098.8 | 558.7 | 1.8 |
| ν3 | 480.3 | 0.1 | 481.5 | 1.1 | 1.2 |
| ν4 | 1192.2 | 282.1 | 1182.6 | 214.4 | −9.6 |
| Benzene | |||||
| ν2 | 1007.1 | 0.0 | 1006.3 | 1.0 | −0.8 |
| ν4 | 678.4 | 115.9 | 680.6 | 128.7 | 2.2 |
| CF3Br | |||||
| ν1 | 1078.6 | 496.1 | 1080.0 | 581.9 | 1.4 |
| ν3 | 361.5 | 0.0 | 360.4 | 1.0 | −1.1 |
| ν4 | 1178.8 | 254.7 | 1169.8 | 243.6 | −9.0 |
| Benzene | |||||
| ν2 | 1007.1 | 0.0 | 1005.9 | 1.6 | −1.2 |
| ν4 | 678.4 | 115.9 | 681.9 | 133.4 | 3.5 |
| CF3I | |||||
| ν1 | 1060.0 | 546.9 | 1063.4 | 625.2 | 3.5 |
| ν3 | 295.1 | 0.3 | 293.3 | 2.6 | −1.8 |
| ν4 | 1162.0 | 227.6 | 1151.8 | 222.2 | −10.2 |
| Benzene | |||||
| ν2 | 1007.1 | 0.0 | 1005.3 | 3.1 | −1.8 |
| ν4 | 678.4 | 115.9 | 683.5 | 141.6 | 5.1 |