imidazole+CHO C4H4N2O
B_056dec31a6 · SMILES O=Cc1cnc[nH]1 · InChIKey ZQEXIXXJFSQPNA-UHFFFAOYSA-N
Cheap level done analytic check agrees
Harmonic frequencies at the cheap level (deck v1: B3LYP and ωB97X, 6-31G*, at the B3LYP geometry)
27 vibrational modes; imaginary modes negative. Shift = ωB97X − B3LYP.
Band heights are not computed for this molecule yet (no dipole derivatives); positions only, at unit height. High wavenumbers on the left; the table below is the same data.
| # | B3LYP (cm⁻¹) | ωB97X (cm⁻¹) | shift |
|---|---|---|---|
| 1 | 151.6 | 178.7 | +27.1 |
| 2 | 192.0 | 206.7 | +14.8 |
| 3 | 299.4 | 315.3 | +16.0 |
| 4 | 505.7 | 510.3 | +4.6 |
| 5 | 601.4 | 632.0 | +30.6 |
| 6 | 654.5 | 668.0 | +13.5 |
| 7 | 688.9 | 710.4 | +21.5 |
| 8 | 775.2 | 785.8 | +10.6 |
| 9 | 840.4 | 877.3 | +36.8 |
| 10 | 872.1 | 897.1 | +25.0 |
| 11 | 933.9 | 941.2 | +7.3 |
| 12 | 1011.0 | 1035.4 | +24.4 |
| 13 | 1026.3 | 1036.8 | +10.6 |
| 14 | 1114.6 | 1127.9 | +13.3 |
| 15 | 1169.7 | 1179.7 | +9.9 |
| 16 | 1271.8 | 1276.2 | +4.4 |
| 17 | 1310.7 | 1329.3 | +18.5 |
| 18 | 1379.7 | 1403.2 | +23.5 |
| 19 | 1404.2 | 1417.7 | +13.5 |
| 20 | 1456.4 | 1484.4 | +28.1 |
| 21 | 1503.8 | 1520.5 | +16.7 |
| 22 | 1601.9 | 1628.7 | +26.8 |
| 23 | 1763.7 | 1798.0 | +34.3 |
| 24 | 2962.4 | 3011.2 | +48.8 |
| 25 | 3262.0 | 3301.0 | +39.0 |
| 26 | 3274.0 | 3313.0 | +39.0 |
| 27 | 3634.4 | 3682.6 | +48.2 |
Second route
Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 1 cm⁻¹; wb97x max |Δω| 12 cm⁻¹.
Provenance
- Releases: layerB_interim_2026-09-25
- Entered the corpus as: cores with one or two substituents, enumerated from the parents (layer B)
- Run: ubuntu-32gb-hel1-18, 2026-09-25 17:38:10 → 2026-09-25 17:44:12, 362 s, peak 1.66 GB, deck 9e27bf8e9348
- Imaginary modes: B3LYP 0, ωB97X 0
- Source files: corpus factory · manifest