Table 2.
Experimental and theoretical vibrational wavenumbers of 2BT.
| Mode | Experimental frequency (cm-1) |
Theoretical frequencies (cm-1) |
IR intensity | Raman activity | Assignments with PED (%) | ||
|---|---|---|---|---|---|---|---|
| FT-IR | FT-Raman | Unscaled | Scaled | ||||
| 1 | 3590 | - | 3772 | 3614 | 126.88 | 172.9 | νOH (100) |
| 2 | 3500 | - | 3217 | 3082 | 0.19 | 88.16 | νCH (99) |
| 3 | 3090 | - | 3194 | 3060 | 14.25 | 321.67 | νCH (95) |
| 4 | 3186 | 3052 | 14.17 | 73.07 | νCH (96) | ||
| 5 | 3176 | 3043 | 3.12 | 121.7 | νCH (96) | ||
| 6 | 3168 | 3035 | 0.16 | 33.34 | νCH (95) | ||
| 7 | 1750 | - | 1777 | 1702 | 538.32 | 286.92 | νOC (82) |
| 8 | 1595 | - | 1633 | 1605 | 9.35 | 130.15 | νCC (63), δHOC (13) |
| 9 | 1570 | 1337 | 1599 | 1572 | 14.26 | 30.23 | νCC (63) |
| 10 | 1510 | 1320 | 1557 | 1531 | 87.17 | 384.99 | νCC (65) |
| 11 | 1410 | 1305 | 1489 | 1464 | 5.77 | 25.6 | νCC (28), δHCC (47) |
| 12 | 1458 | 1433 | 27.56 | 64.47 | δHOC (10), δHCC (45) | ||
| 13 | 1370 | 1280 | 1375 | 1352 | 65.32 | 7.99 | νCC (39), δHOC (17) |
| 14 | 1300 | 1270 | 1347 | 1324 | 81.07 | 12.9 | νCC (48), δHOC (26) |
| 15 | 1338 | 1315 | 0.58 | 133.47 | νCC (38), δHCC (17), δCCC (12) | ||
| 16 | 1210 | 1253 | 1273 | 1251 | 8.85 | 25.04 | νCC (18), δHOC (13), δHCC (19) |
| 17 | - | 1240 | 1230 | 1209 | 50.92 | 3.79 | δHOC (18), νCH (23) |
| 18 | 1187 | 1167 | 17.29 | 11.03 | δHCC (65) | ||
| 19 | 1140 | - | 1166 | 1146 | 351.17 | 52.74 | νCC (21), δHOC (20), νCH (38) |
| 20 | 1152 | 1132 | 3.51 | 38.13 | νCC (24), δHOC (51) | ||
| 21 | 1081 | 1063 | 26.21 | 36.76 | νSC (49), δCCC (15) | ||
| 22 | 1042 | 1024 | 29.41 | 45.13 | νCC (67), δHCC (11) | ||
| 23 | 1005 | - | 1024 | 1007 | 70.77 | 5.72 | νSC (70) |
| 24 | 996 | 979 | 0 | 0.06 | τHCCH (91) | ||
| 25 | 960 | 944 | 2.15 | 0.13 | τHCCH (89) | ||
| 26 | 880 | - | 889 | 874 | 12.09 | 1.9 | τHCCC (87) |
| 27 | 873 | 858 | 0.17 | 5.19 | νSC (12), νSC (10), δCCC (47) | ||
| 28 | 859 | 844 | 0.76 | 0.3 | τHCCS (91) | ||
| 29 | 770 | - | 773 | 760 | 80.66 | 0.25 | τHCCC (24), γOCOC (61) |
| 30 | 754 | 741 | 7.71 | 0.17 | τHCCC (64), γOCOC (26) | ||
| 31 | 732 | 720 | 9.5 | 22.68 | δCCC (16), νSC (51) | ||
| 32 | 720 | - | 725 | 713 | 25.08 | 0.08 | τCCCC (80) |
| 33 | 705 | - | 709 | 697 | 9 | 1.85 | νSC (54), δCCO (14) |
| 34 | 670 | - | 675 | 664 | 33.61 | 7.08 | δOCO (74) |
| 35 | 589 | 579 | 26.08 | 3.79 | δOCO (78) | ||
| 36 | 610 | - | 574 | 564 | 12.27 | 1.69 | τHOCC (92) |
| 37 | 560 | - | 545 | 536 | 66.08 | 1.41 | τHOCC (88) |
| 38 | 497 | 489 | 0.85 | 11.53 | δCSC (66) | ||
| 39 | 467 | 459 | 31.82 | 0.12 | γSCCC (87) | ||
| 40 | 457 | 449 | 4.95 | 5.24 | νSC (19), δCCO (59) | ||
| 31 | 426 | 419 | 0.02 | 0.32 | τCCCC (80) | ||
| 42 | 340 | 334 | 0.55 | 0.58 | δCCC (70) | ||
| 43 | 327 | 321 | 2.92 | 4.91 | νCC (13), δCCC (32), νSC (17) | ||
| 44 | 252 | 248 | 0.16 | 0.27 | γCCSC (94) | ||
| 45 | 197 | 194 | 0.05 | 0.15 | τCCCS (88) | ||
| 46 | 138 | 136 | 2.47 | 0.31 | δCCC (85) | ||
| 47 | 87 | 86 | 0.47 | 1.74 | τCCCC (92) | ||
| 48 | 69 | 68 | 0.54 | 0.07 | τCCCO (93) | ||
(ν- stretching; δ- in plane bending; γ- out of plane bending; τ- torsion).