pyridine+CH3+ethynyl C8H7N
B_1274d1530a · SMILES C#Cc1cccc(C)n1 · InChIKey RUFOVPQUNXLVFW-UHFFFAOYSA-N
Cheap level done imaginary mode, second route pending
finite-difference Hessian noisy
finite-difference Hessian noisy (analytic check differs > 15 cm⁻¹). The finite-difference Hessian and the analytic Hessian of the same geometry differ by more than 15 cm⁻¹ on at least one frequency; the numerical route is the noisy one.Harmonic frequencies at the cheap level (deck v1: B3LYP and ωB97X, 6-31G*, at the B3LYP geometry)
42 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 | -39.1 | -87.8 | -48.7 |
| 2 | 139.3 | 161.4 | +22.1 |
| 3 | 143.3 | 163.4 | +20.1 |
| 4 | 199.9 | 212.3 | +12.4 |
| 5 | 345.5 | 352.1 | +6.7 |
| 6 | 380.4 | 398.9 | +18.5 |
| 7 | 451.7 | 465.8 | +14.1 |
| 8 | 491.2 | 496.6 | +5.4 |
| 9 | 547.2 | 554.4 | +7.3 |
| 10 | 566.5 | 575.7 | +9.2 |
| 11 | 586.9 | 640.1 | +53.2 |
| 12 | 631.4 | 663.9 | +32.6 |
| 13 | 633.9 | 682.3 | +48.4 |
| 14 | 718.8 | 725.9 | +7.0 |
| 15 | 754.4 | 769.5 | +15.1 |
| 16 | 813.6 | 834.7 | +21.1 |
| 17 | 916.6 | 938.8 | +22.1 |
| 18 | 932.7 | 945.7 | +13.1 |
| 19 | 998.7 | 1016.5 | +17.7 |
| 20 | 1005.9 | 1027.2 | +21.4 |
| 21 | 1023.7 | 1030.3 | +6.6 |
| 22 | 1072.3 | 1081.7 | +9.4 |
| 23 | 1121.7 | 1129.2 | +7.5 |
| 24 | 1192.7 | 1186.6 | -6.1 |
| 25 | 1243.8 | 1259.8 | +16.0 |
| 26 | 1289.0 | 1268.6 | -20.4 |
| 27 | 1311.2 | 1314.9 | +3.6 |
| 28 | 1431.7 | 1442.7 | +11.0 |
| 29 | 1445.4 | 1469.0 | +23.5 |
| 30 | 1492.5 | 1512.1 | +19.6 |
| 31 | 1515.2 | 1517.9 | +2.7 |
| 32 | 1516.4 | 1524.0 | +7.5 |
| 33 | 1630.5 | 1667.5 | +36.9 |
| 34 | 1633.6 | 1672.2 | +38.5 |
| 35 | 2235.1 | 2265.9 | +30.8 |
| 36 | 3049.1 | 3084.1 | +35.0 |
| 37 | 3100.6 | 3150.0 | +49.4 |
| 38 | 3160.6 | 3206.0 | +45.4 |
| 39 | 3189.3 | 3232.8 | +43.5 |
| 40 | 3204.9 | 3248.0 | +43.2 |
| 41 | 3224.0 | 3267.0 | +43.0 |
| 42 | 3495.1 | 3529.7 | +34.6 |
Second route
Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 4 cm⁻¹; wb97x max |Δω| 136 cm⁻¹.
Provenance
- Releases: none yet
- Entered the corpus as: cores with one or two substituents, enumerated from the parents (layer B)
- Run: ubuntu-32gb-hel1-16, 2026-09-27 00:17:42 → 2026-09-27 00:33:43, 961 s, peak 2.44 GB, deck 9e27bf8e9348
- Imaginary modes: B3LYP 1, ωB97X 1
- Source files: corpus factory · manifest